# Go Math Grade 4 Answer Key Chapter 3 Multiply 2-Digit Numbers

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## Go Math Grade 4 Solution Key Pdf Chapter 3 Multiply 2-Digit Numbers

With the help of HMH Go Math Grade 4 Answer Key Ch 3, you can learn the easy methods to solve problems. Answer Key for HMH Go Math Grade 4 Chapter 3 Multiply 2-Digit Numbers consists of all the questions from practice tests, exercises, assessments tests. You guys are recommended to solve the 4th grade Go Math Answers of Chapter 3 Multiply 2-Digit Numbers regularly & attempt the exams with confidence. The topics covered in the Go Math HMH grade 4 Solutions are designed perfectly & in an understandable way.

Lesson 1: Multiply by Tens

Lesson 2: Estimate Products

Lesson 3: Investigate • Area Models and Partial Products

Lesson 4: Multiply Using Partial Products

Mid-Chapter Checkpoint

Lesson 5: Multiply with Regrouping

Lesson 6: Choose a Multiplication Method

Lesson 7: Problem Solving • Multiply 2-Digit Numbers

Review/Test

### Common Core – Page No. 149

Multiply by Tens

Choose a method. Then find the product.

Question 1.
16 × 60 = 960
Use the halving-and-doubling strategy.
Find half of 16: 16 ÷ 2 = 8.
Multiply this number by 60: 8 × 60 = 480
Double this result: 2 × 480 = 960

960

Explanation:
Use the halving-and-doubling strategy.
Find half of 16: 16 ÷ 2 = 8.
Multiply this number by 60: 8 × 60 = 480
Double this result: 2 × 480 = 960

Question 2.
80 × 22 = ______

1760

Explanation:
By using the place value method, Multiply 80 x 22
You can think of 80 as 8 tens
80 x 22 = (22 x 8) tens
= 176 tens
= 176 x 10 = 1760
80 x 22 = 1760

Question 3.
30 × 52 = ______

1560

Explanation:
Use the Associative Property
You can think of 30 as 3 x 10
30 x 52 = (3 x 10) x 52
= 3 x (10 x 52)
=  3 x 520
= 1560
30 x 52 = 1560

Question 4.
60 × 20 = ______

1200

Explanation:
60 x 20
Use the halving and doubling strategy
half of the 60 to make the problem simpler
60/ 2 = 30
Multiply 30 with 20
30 x 20 = 600
Double the 600
2 x 600= 1200
60 x 20 = 1200

Question 5.
40 × 35 = ______

1400

Explanation:
By using the Associative Property 40 x 35
You can think of 40 as 4 x 10
40 x 35 = (4 x 10) x 35
= 4  x (10 x 35)
= 4 x 350
= 1400
40 x 35 = 1400

Question 6.
10 × 90 = ______

900

Explanation:
By using the place value method, Multiply 10 x 90
You can think of 90 as 9 tens
10 x 90 = (10 x 9) tens
= 90 tens
= 10 x 90 = 900

Question 7.
31 × 50 = ______

1,550

Explanation:
Use the place value method to multiply 31 x 50
You can think of 50 as 5 tens
31 x 50 = 31 x 5 tens
= 155 tens
= 1,550
31 x 50 = 1,550

Problem Solving

Question 8.
Kenny bought 20 packs of baseball cards. There are 12 cards in each pack. How many cards did Kenny buy?
______ cards

240 cards

Explanation:
From the given data,
Kenny bought 20 packs of basketball cards
There are 12 cards in each pack = 12 x 20 cards
Use the associative property
You can write 20 as 2 x 10
12 x 20 = 12 x (2 x 10)
= (12 x 2) x 10
= (24) x 10
= 240 cards
Kenny bought 240 cards

Question 9.
The Hart family drove 10 hours to their vacation spot. They drove an average of 48 miles each hour. How many miles did they drive in all?
______ miles

480 miles

Explanation:
As per the given data,
Hart family drove 10 hours to their vacation spot
Average speed per each hour is = 48 miles
Total miles = 48 x 10
Use the halving and doubling strategy
Half of the 48 to make the problem simpler
48/ 2 = 24
Multiply 24 with 10 = 24x 10 = 240
Double the value = 2 x 240 = 480 miles
Total miles drove by hart family = 480 miles.

### Common Core – Page No. 150

Lesson Check

Question 1.
For the school play, 40 rows of chairs are set up. There are 22 chairs in each row. How many chairs are there in all?
Options:
a. 800
b. 840
c. 880
d. 8,800

c. 880

Explanation:
As per the given data
For the school play, 40 rows of chairs are available. 22 chairs are available in each row.
Then total chairs in school play are = 22 x 40
By using the place value method
You can think of 40 as 4 tens
22 x 40 = 22 x 4 tens
= 88 tens
= 880
Total chairs in school are = 880

Question 2.
At West School, there are 20 classrooms. Each classroom has 20 students. How many students are at West School?
Options:
a. 40
b. 400
c. 440
d. 4,000

b. 400

Explanation:
From the given data,
Total classrooms in west school = 20
Number of students per each classroom = 20
Then, total students at West School = 20 x 20
By using the associative property
You can think of 20 as 2 x 10
20 x 20 = 20 x (2 x 10)
= (20 x 2) x 10
=(40) x 10
=400
Total number of students at West School = 400

Spiral Review

Question 3.
Alex has 48 stickers. This is 6 times the number of stickers Max has. How many stickers does Max have?
Options:
a. 6
b. 7
c. 8
d. 9

c. 8

Explanation:
As per the give data,
Alex has 48 stickers
That means, X= 48
This is 6 times the number of stickers max has = Y = 6X = 48
Then, number of stickers with Max = Y = X = 48/6 = 8
Number of stickers with Max = Y = 8 Stickers.

Question 4.
Ali’s dog weighs 8 times as much as her cat. Together, the two pets weigh 54 pounds. How much does Ali’s dog weigh?
Options:
a. 6 pounds
b. 42 pounds
c. 46 pounds
d. 48 pounds

d. 48 pounds

Explanation:
From the given data,
Ali’s cat weight = X
Ali’s dog weight = 8 times as much as Ali’s cat = 8X
Together, the two pets weight = (X+8X) = 54 pounds
= 9X = 54 pounds
= X = 54/9 pounds = 6 pounds
Then, Ali’s dog weight = 8X =8 x 6 = 48 pounds.

Question 5.
Allison has 3 containers with 25 crayons in each. She also has 4 boxes of markers with 12 markers in each box. She gives 10 crayons to a friend. How many crayons and markers does Allison have now?
Options:
a. 34
b. 113
c. 123
d. 133

b. 113

Explanation:
As per the given data,
Allison has 3 containers with 25 crayons in each = X = 3 x 25 = 75
Allison has 4 boxes of markers with 12 markers in each box = Y = 4 x 12 = 48
Allison gives 10 crayons to a friend = Z = 75-10 = 65
Now, total number of crayons and markers with Allison = Y + Z = 48 + 65 = 113

Question 6.
The state of Utah covers 82,144 square miles. The state of Montana covers 145,552 square miles. What is the total area of the two states?
Options:
a. 63,408 square miles
b. 223,408 square miles
c. 227,696 square miles
d. 966,992 square miles

c. 227,696 square miles

Explanation:
From the given data,
The state of Utah covers 82,144 square miles
The state of Montana covers 145,552 square miles
Then, Total area of the two states = 82,144 + 145,552
The total area of two states = 227,696 square miles.

### Page No. 153

Question 1.
To estimate the product of 62 and 28 by rounding, how would you round the factors? What would the estimated product be?

1800

Explanation:
By using rounding and mental math
Estimate 62 x 28
Firstly, round each factor
62 x 28

60 x 30
Use mental math
6 x 3 = 18
60 x 30 = 1800
So, estimated product of 62 and 28 = 1800

Estimate the product. Choose a method.

Question 2.
96 × 34
Estimate: _____

3000

Explanation:
Use mental math and compatible numbers
96 x 34

100 x 30
Use mental math
1 x 30 = 30
100 x 30= 3000

Question 3.
47 × $39 Estimate:$ _____

2000

Explanation:
Round to the nearest ten
47 x $39 50 x$40
50 x $4 =$200
50 x $40 = 2000 Question 4. 78 × 72 Estimate: _____ Answer: 5600 Explanation: Use rounding and mental math Round each factor 78 x 72 80 x 70 Use mental math 8 x 7 = 56 80 x 70 = 5600 Question 5. 41 × 78 Estimate: _____ Answer: 3200 Explanation: Use compatible numbers and mental math 41 x 78 40 x 80 Use mental math 40 x 8 = 320 40 x 80 = 3200 Question 6. 51 × 73 Estimate: _____ Answer: 3500 Explanation: Round to the nearest ten 51 x 73 50 x 70 = 3500 Question 7. 34 × 80 Estimate: _____ Answer: 2400 Explanation: Round each factor 34 x 80 30 x 80 3 x 8 = 240 30 x 80 = 2400 Practice: Copy and Solve Estimate the product. Choose a method. Question 8. 61 × 31 Estimate: _____ Answer: 1800 Explanation: Round to the nearest ten 61 x 31 60 x 30 = 1800 Question 9. 52 × 68 Estimate: _____ Answer: 3500 Explanation: Round each factor 52 x 68 50 x 70 Use mental math 5 x 7 =35 50 x 70 = 3500 Question 10. 26 × 44 Estimate: _____ Answer: 1200 Explanation: Round to the nearest tens 26 x 44 30 x 40 = 1200 Question 11. 57 ×$69
Estimate: $_____ Answer:$4200

Explanation:
Round each factor
57 x $69 60 x$70
Use mental math
6 x $7 =$42
60 x $70 =$4200

Find two possible factors for the estimated product.

Question 12.
2,800
Type below:
___________

2800

Explanation:
Let us consider 7 x 4 = 28
70 x 40 = 2800

Question 13.
8,100
Type below:
___________

8,100

Explanation:
Let us take 9 x 9 = 81
90 x 90 = 8,100

Question 14.
5,600
Type below:
___________

5,600

Explanation:
Let us consider 7 x 8 = 56
70 x 80 = 5,600

Question 15.
2,400
Type below:
___________

2,400

Explanation:
Let us take 4 x 6 = 24
40 x 60 = 2400
Or 3 x 8 = 24
30 x 80 = 2,400

Question 16.
Mr. Parker jogs for 35 minutes each day. He jogs 5 days in week 1, 6 days in week 2, and 7 days in week 3. About how many minutes does he jog?

Explanation:
From the given data,
Mr. Parker jogs per day = 35 minutes
He jogs 5 days in week 1 = 5 x 35 = 175 minutes
6 days in week 2 = 6 x 35 = 210 minutes
7 days in week 3 = 7 x 35 = 245 minutes
Total minutes of jog by Mr. Parker = week 1 + week 2 + week 3
= 175 + 210 + 245
= 630 minutes
So, total minutes of jog by Mr. Parker = 630 minutes

Question 17.
There are 48 beads in a package. Candice bought 4 packages of blue, 9 packages of gold, 6 packages of red, and 2 packages of silver beads. About how many beads did Candice buy?

Explanation:
As per the given data,
48 beads are there in a package
Candice bought 4 packages of blue beads = 4 x 48 = 192
9 packages of gold beads = 9 x 48 = 432
6 packages of red beads = 6 x 48 = 288
2 packages of silver beads = 2 x 48 = 96
Total beads bought by Candice = 192 + 432 + 288 + 96
So, total beads bought by Candice = 1008.

### Page No. 154

Question 18.
On average, a refrigerator door is opened 38 times each day. Len has two refrigerators in his house. Based on this average, about how many times in a 3-week period are the refrigerator doors opened?

Explanation:
From the given data,
On average, a refrigerator door is opened per day = 38 times
3-week period = 7 x 3 = 21
Then, a refrigerator door is opened per 21 days = 21 x 38 = 798 times
Len has 2 refrigerators in his house
Then, two refrigerators door are opened per 21 days = 2 x 798
= 1596 times
So, in a 3 – week period refrigerator door is opened about 1600 times

Question 19.
The cost to run a refrigerator is about $57 each year. About how much will it have cost to run by the time it is 15 years old? about$ _____

1200

Explanation:
As per the data,
The cost to run a refrigerator per each year = $57 Cost to run a refrigerator by the time it is 15 years old =$57 * 15
Round to the nearest tens
$57 x 15$60 x 20
Use mental math
$6 x 2 = 12$ 60 x 20 = 1200

Question 20.
If Mel opens his refrigerator door 36 times every day, about how many times will it be opened in April? Will the exact answer be more than or less than the estimate? Explain.
Type below:
___________

1200

Explanation:
From the given data,
Mel opens his refrigerator door per day = 36 times
Number of days in April month = 30 days
Refrigerator door opened in April month = 36 * 30
Round the factors
36 x 30

40 x 30 = 1200

Question 21.
Represent a Problem What question could you write for this answer? The estimated product of two numbers, that are not multiples of ten, is 2,800.
Type below:
___________

2800

Explanation:
Let us take
1.
38 × 21
↓        ↓
40 × 20 = 800
2,800 = 42 x 68
↓    ↓
40 x  70 = 2800

Question 22.
Which is a reasonable estimate for the product? Write the estimate. An estimate may be used more than once.

26 × 48 __________
28 × 21 __________
21 × 22 __________
51 × 26 __________

25 x 50 = 1250
30 x 20 = 600
20 x 20 = 400
50 x 25 = 1250

Explanation:
26 x 48 -> 25 x 50 = 1250
28 x 21 -> 30 x 20 = 600
21 x 22 -> 20 x 20 = 400
51 x 26 -> 50 x 25 = 1250

### Common Core – Page No. 155

Estimate Products
Estimate the product. Choose a method.

Question 1.
38 × 21
38 × 21
↓       ↓
40 × 20
800

800

Explanation:
38 × 21
↓        ↓
40 × 20
800

Question 2.
63 × 19
Estimate: _____

1200

Explanation:
63 x 19

60 x 20 = 1200
Estimated product of 63 x 19 = 1200

Question 3.
27 × $42 Estimate:$ _____

$1000 Explanation: 27 ×$42

25 x $40 =$1000
Estimated Product of 25 x $42 =$1000

Question 4.
73 × 67
Estimate: _____

4900

Explanation:
73 × 67

70 x 70 = 4900
Estimated Product of 73 x 67 = 4900

Question 5.
37 × $44 Estimate:$ _____

$1600 Explanation: 37 ×$44

40 x $40 =$1600
Estimated Product of 37 x $44 =$1600

Question 6.
85 × 71
Estimate: _____

6300

Explanation:
85 × 71

90 x 70 = 6300
Estimated Product of 85 x 71 = 6300

Question 7.
88 × 56
Estimate: _____

4950

Explanation:
88 × 56

90 x 55 = 4950
Estimated Product of 90 x 55 = 4950

Question 8.
97 × 13
Estimate: _____

1,000

Explanation:
97 × 13

100 x 10 = 1,000

Question 9.
92 × 64
Estimate: _____

5850

Explanation:
92 × 64

90 x 65 = 5850

Problem Solving

Question 10.
A dime has a diameter of about 18 millimeters. About how many millimeters long would a row of 34 dimes be?

Explanation:
From the given data,
A dime has a diameter of about 18 millimeters
Then, 34 dimes diameter = 18 * 34
18 x 34

20 x 30 = 600
So, 34 dimes have a diameter of about 600 millimeters long

Question 11.
A half-dollar has a diameter of about 31 millimeters. About how many millimeters long would a row of 56 half-dollars be?

1800 millimeters

Explanation:
As per the given data,
A half – dollar has a diameter of about 31 millimeters
Then, 56 half-dollars diameter = 31 * 56
31 * 56

30 * 60
So, 56 half-dollars have a diameter of about 1800 millimeters long.

### Common Core – Page No. 156

Lesson Check

Question 1.
Which is the best estimate for the product
43 × 68?
Options:
a. 3,500
b. 2,800
c. 2,400
d. 280

b. 2,800

Explanation:
Round to the nearest tens
43 x 68

40 x 70
Use mental math
4 x 7 = 28
40 x 70 = 2800
Estimated product of 43 x 68 = 2800

Question 2.
Marissa burns 93 calories each time she plays fetch with her dog. She plays fetch with her dog once a day. About how many calories will Marissa burn playing fetch with her dog in 28 days?
Options:
a. 4,000
b. 2,700
c. 2,000
d. 270

b. 2,700

Explanation:
From the given data,
Marissa burned calories each time when she plays fetch with her dog= 93 calories
Then, Marissa burned calories in 28 days while playing fetch with her dog = 28 x 93
Round to the nearest tens
28 x 93

30 x 90
Then, estimated burned calories in 28 days by Marissa = 2700 calories

Spiral Review

Question 3.
Use the model to find 3 × 126.

Options:
a. 368
b. 378
c. 468
d. 478

b. 378

Explanation:
From the above Figure,
3 x 126 = 3 x 100 + 3 x 20 + 3 x 6
= 300 + 60 + 18
= 378
3 x 126 = 378

Question 4.
A store sells a certain brand of jeans for $38. One day, the store sold 6 pairs of jeans of that brand. How much money did the store make from selling the 6 pairs of jeans? Options: a.$188
b. $228 c.$248
d. $288 Answer: b.$228

Explanation:
As per the given data,
A store sells a certain brand of jeans for rupees = $38 One day, the store sold 6 pairs of jeans of that brand = 6 x$38
6 x $38 =$228
The total amount of 6 pairs of jeans = $228 Question 5. The Gateway Arch in St. Louis, Missouri, weighs about 20,000 tons. Which amount could be the exact number of tons the Arch weighs? Options: a. 31,093 tons b. 25,812 tons c. 17,246 tons d. 14,096 tons Answer: c. 17,246 tons Explanation: From the given data, The Gateway Arch in St.Louis, Missouri weight = about 20,000 tons From the available options, 17,246 tons is closer to 20,000 tons Then, the exact number of tons the Arch weighs = 17,246 tons Question 6. Which is another name for 23 ten thousands? Options: a. 23,000,000 b. 2,300,000 c. 230,000 d. 23,000 Answer: c. 230,000 Explanation: As per the data, Another name for 23 ten thousands = 23 x 10,000 = 230,000 Another name for 23 ten thousand = 2,30,000 ### Page No. 159 Find the product. Question 1. 16 × 19 16 × 19 = _____ Answer: 304 Explanation: 16 x 19 = 304 Question 2. 18 × 26 18 × 26 = _____ Answer: 468 Explanation: 200 + 160 + 60 + 48 = 468 Question 3. 27 × 39 27 × 39 = ______ Answer: 1,053 Explanation: 600 + 210 + 180 +63 = 1053 Draw a model to represent the product. Then record the product. Question 4. 14 × 16 = ______ Answer: 224 Explanation: 100 + 40 + 60 + 24 = 224 Question 5. 23 × 25 = ______ Answer: 575 Explanation: 400 + 60 + 100 + 15 = 575 Question 6. Explain how modeling partial products can be used to find the products of greater numbers. Type below: __________ Answer: You can use mental math to find the partial products and then find the sum of the partial products. Explanation: Question 7. Emma bought 16 packages of rolls for a party. There were 12 rolls in a package. After the party there were 8 rolls left over. How many rolls were eaten? Explain. ______ rolls Answer: 184 rolls were eaten Explanation: From the given data, Emma bought 16 packages of rolls for a party There were 12 rolls in a package Then, total rolls = 16 x 12 = 192 100 + 60 + 20 + 12 =192 After the party there were 8 rolls left over Then, total eaten rolls are = 192 – 8 = 184 ### Page No. 160 Question 8. Jamal and Kim used different ways to solve 12 × 15 by using partial products. Whose answer makes sense? Whose answer is nonsense? Explain your reasoning. Jamal’s Work 100 + 20 + 10 = 130 Kim’s Work 120 + 60 = 180 a. For the answer that is nonsense, write an answer that makes sense. Type below: __________ Answer: a. Jamal’s work makes nonsense. 100 + 20 + 50 + 10 = 180 it makes sense Question 8. b. Look at Kim’s method. Can you think of another way Kim could use the model to find the product? Explain. Type below: __________ Answer: Other method: 12 x 15 10 x 12 = 120 5 x 12 = 60 120 + 60 = 180. Explanation: Kim follows another method to find 12 x 15 That is, 100 + 50 = 150 20 + 10 = 30 Then, 150 + 30 =180 12 x 15 = 180 Question 9. Look at the model in 8b. How would the partial products change if the product was 22 × 15? Explain why you think the products changed. Type below: __________ Answer: 330 Explanation: Following the 8b method 22 x 15 =330 200 + 100 = 300 20 + 10 = 30 Now, 300 + 30 = 330 Finally, 22 x 15 = 330 The factor of 15 is increased in present problem. So, the product also increases for 15 x 22. ### Common Core – Page No. 161 Area Models and Partial Products Draw a model to represent the product. Then record the product. Question 1. 13 × 42 Answer: Question 2. 18 × 34 = ______ Answer: 300 + 40 + 240 + 32 = 612 Question 3. 22 × 26 = ______ Answer: 400 + 120 + 40 + 12 = 572 Question 4. 1 5 × 33 = ______ Answer: 300 + 30 + 150 + 15 = 495 Question 5. 23 × 29 = ______ Answer: 400 + 180 + 60 + 27 = 667 Question 6. 19 × 36 = ______ Answer: 300 + 60 + 270 + 54 = 684 Problem Solving Question 7. Sebastian made the following model to find the product 17 × 24. Is his model correct? Explain. a. yes b. no Answer: b. no Explanation: 200 + 40 + 140 + 28 = 408 Question 8. Each student in Ms. Sike’s kindergarten class has a box of crayons. Each box has 36 crayons. If there are 18 students in Ms. Sike’s class, how many crayons are there in all? ______ crayons Answer: 648 crayons Explanation: From the given information, Each student in Ms.Sike’s kindergarten class has a box of crayons Crayons in each box = 36 Crayons Number of students in Mr.Sike’s class = 18 students Total crayons = 18 x 36 300 + 60 + 240 + 48 = 648 ### Common Core – Page No. 162 Lesson Check Question 1. Which product does the model below represent? Options: a. 161 b. 230 c. 340 d. 391 Answer: d. 391 Explanation: 200 + 30 + 140 + 21 = 391 17 x 23 = 391 Question 2. Which product does the model below represent? Options: a. 219 b. 225 c. 244 d. 275 Answer: b. 225 Explanation: 130 + 20 + 65 + 10 = 225 15 x 15 = 225 Spiral Review Question 3. Mariah builds a tabletop using square tiles. There are 12 rows of tiles and 30 tiles in each row. How many tiles in all does Mariah use? Options: a. 100 b. 180 c. 360 d. 420 Answer: c. 360 Explanation: From the given data, Mariah builds a tabletop using square tiles Square contains 12 rows of tiles and 30 tiles in each row = 12 x 30 12 x 30 = 360 tiles Total tiles used by Mariah = 360 tiles Question 4. Trevor bakes 8 batches of biscuits, with 14 biscuits in each batch. He sets aside 4 biscuits from each batch for a bake sale and puts the rest in a jar. How many biscuits does Trevor put in the jar? Options: a. 112 b. 80 c. 50 d. 32 Answer: b. 80 Explanation: As per the given data, Number of biscuits baked by Trevor = 8 batches Number of biscuits in each batch = 14 biscuits So, total biscuits = 14 x 8 = 112 Trevor sets aside 4 biscuits from each batch for a bake = 8*4 = 32 biscuits are aside for a bake Trevor kept rest of biscuits in a jar = 112 – 32 = 80 So, 80 biscuits are put in the jar by the Trevor Question 5. Li feeds her dog 3 cups of food each day. About how many cups of food does her dog eat in 28 days? Options: a. 60 cups b. 70 cups c. 80 cups d. 90 cups Answer: c. 80 cups Explanation: As per the given data, Li feeds her dog per day = 3 cups of food Then, Li feeds her dog for 28 days = 3 x 28 = 84 cups of food So, Li feeds her dog with 84 cups of food in 28 days Question 6. Which symbol makes the number sentence true? 4 ■ 0 = 0 Options: a. + b. – c. × d. ÷ Answer: c. × Explanation: 4 x 0 = 0 ### Page No. 165 Question 1. Find 24 × 34. _____ Answer: 816 Explanation: Question 2. 1 2 × 1 2 ——– _____ Answer: 144 Explanation: Question 3. 3 1 × 2 4 ——- _____ Answer: 744 Explanation: Question 4. 2 5 × 4 3 ——- _____ Answer: 1,075 Explanation: Question 5. 3 7 × 2 4 ——- _____ Answer: 888 Explanation: Question 6. 5 4 × 1 5 ——- _____ Answer: 810 Explanation: Question 7. 8 7 × 1 6 ——- _____ Answer: 1,392 Explanation: Question 8. 6 2 × 5 6 ——- _____ Answer: 3,472 Explanation: Question 9. 4 9 × 6 3 ——- _____ Answer: 3,087 Explanation: Practice: Copy and Solve Record the product. Question 10. 38 × 47 _____ Answer: 1,786 Explanation: Question 11. 46 × 27 _____ Answer: 1,242 Explanation: Question 12. 72 × 53 _____ Answer: 3,816 Explanation: Question 13. 98 × 69 _____ Answer: 6,762 Explanation: Question 14. 53 × 68 _____ Answer: 3,604 Explanation: Question 15. 76 × 84 _____ Answer: 6,384 Explanation: Question 16. 92 × 48 _____ Answer: 4,416 Explanation: Question 17. 37 × 79 _____ Answer: 2,923 Explanation: Reason Abstractly Algebra Find the unknown digits. Complete the problem. Question 18. Type below: ___________ Answer: 1,824 Explanation: Question 19. Type below: ___________ Answer: 7,954 Explanation: Question 20. Type below: ___________ Answer: 1,908 Explanation: Question 21. Type below: ___________ Answer: 952 Explanation: ### Page No. 166 Use the picture graph for 22–24. Question 22. Use Graphs A fruit-packing warehouse is shipping 15 boxes of grapefruit to a store in Santa Rosa, California. What is the total weight of the shipment? ______ pounds Answer: 1275 pounds Explanation: From the given data, A fruit packing warehouse is shipping 15 boxes of grapefruit to store in Santa Rose, California Grapefruit weight per box = 85 pounds Total weight of the shipment = 85 x 15 So, the total weight of the shipment = 1275 pounds Question 23. How much less do 13 boxes of tangelos weigh than 18 boxes of tangerines? ______ pounds Answer: 450 pounds Explanation: As per the given data, Tangelos weight per box = 90 pounds Then, the weight of the 13 boxes of tangelos = 90 x 13 And, the weight of the 18 boxes of tangelos = 90 x 18 1620 – 1170 = 450 So, 13 boxes of tangelos weight are 450 pounds less than 18 boxes of tangelos weight Question 24. What is the weight of 12 boxes of oranges? ______ pounds Answer: 1,080 pounds Explanation: The weight of the oranges per box = 90 pounds then, weight of 12 boxes oranges = 90 x 12 So, weight of 12 boxes oranges = 1,080 pounds Question 25. Each person in the United States eats about 65 fresh apples each year. Based on this estimate, how many apples do 3 families of 4 eat each year? ______ apples Answer: 780 apples Explanation: From the given data, Each person in the united states eats fresh apples per year = 65 3 families of 4 persons = 3 x 4 = 12 persons Then, the number of apples eat by 12 persons = 65 x 12 So, the total number of apples eat by 12 persons per year = 780 Question 26. The product 26 × 93 is greater than 25 × 93. How much greater? Explain how you know without multiplying. ______ Answer: The difference is 93 26 x 93 is one more group of 93 than 25 x 93 Question 27. Margot wants to use partial products to find 22 × 17. Write the numbers in the boxes to show 22 × 17. Type below: __________ Answer: Explanation: 22 x 17 (20 + 2) x 17 20 x 17 + 2 x 17 20 x (10 + 7) + 2 x (10 + 7) (20 x 10) + (20 x 7) + (2 x 10) + (2 x 7) ### Common Core – Page No. 167 Multiply Using Partial Products Record the product. Question 1. 2 3 × 7 9 ——— 1, 4 0 0 2 1 0 1 8 0 + 2 7 ——– 1, 8 1 7 Answer: 1, 8 1 7 Explanation: 2 3 × 7 9 ——— 1, 4 0 0 2 1 0 1 8 0 + 2 7 ——– 1, 8 1 7 Question 2. 5 6 × 3 2 ——- _______ Answer: 1,792 Explanation: Question 3. 8 7 × 6 4 ——- _______ Answer: 5,568 Explanation: Question 4. 3 3 × 2 5 ——- _______ Answer: 825 Explanation: Question 5. 9 4 × 1 2 ——- _______ Answer: 1,128 Explanation: Question 6. 5 1 × 7 7 ——- _______ Answer: 3,927 Explanation: Question 7. 6 9 × 4 9 ——- _______ Answer: 3,381 Explanation: Question 8. 8 6 × 8 4 ——- _______ Answer: 7,224 Explanation: Question 9. 9 8 × 4 2 ——- _______ Answer: 4,116 Explanation: Question 10. 7 3 × 3 7 ——- _______ Answer: 2,701 Explanation: Question 11. 8 5 × 5 1 ——- _______ Answer: 4,335 Explanation: Problem Solving Question 12. Evelyn drinks 8 glasses of water a day, which is 56 glasses of water a week. How many glasses of water does she drink in a year? (1 year = 52 weeks) _______ glasses Answer: 2,912 glasses Explanation: As per the given data, Evelyn drinks 8 glasses of water a day Evelyn drinks water per week = 56 glasses Then, the number of glasses per 52 weeks = 52 x 56 Total number of glasses of water drink by Evelyn per year = 2912 glasses of water Question 13. Joe wants to use the Hiking Club’s funds to purchase new walking sticks for each of its 19 members. The sticks cost$26 each. The club has $480. Is this enough money to buy each member a new walking stick? If not, how much more money is needed? Is the money enough? _______ How much more is needed? _______ Answer: This amount is not enough to buy walking sticks Still,$14 amount is needed to buy walking sticks

Explanation:
From the given data,
Joe wants to use the Hiking club funds to purchase new walking sticks for each of its 19 members
Cost per each stick = $26 Total walking sticks cost per 19 members =$26 x 19

Total cost for walking sticks for 19 members = $494 The club has =$480
This amount is not enough to buy walking sticks
Still, $14 amount is needed to buy walking sticks ### Common Core – Page No. 168 Lesson Check Question 1. A carnival snack booth made$76 selling popcorn in one day. It made 22 times as much selling cotton candy. How much money did the snack booth make selling
cotton candy?
Options:
a. $284 b.$304
c. $1,562 d.$1,672

d. $1,672 Explanation: As per the given data, A carnival snack booth made popcorn in one day =$76
It made 22 times as much selling cotton candy
Then, total selling cotton candy made by snack booth = $76 x 22 So,$1672 money snack booth will get for selling cotton candy

Question 2.
What are the partial products of
42 × 28?
Options:
a. 800, 80, 40, 16
b. 800, 16
c. 800, 40, 320, 16
d. 80, 16

c. 800, 40, 320, 16

Explanation:

So, partial products of 42 x 28 are 800, 40, 320, 16

Spiral Review

Question 3.
Last year, the city library collected 117 used books for its shelves. This year, it collected 3 times as many books. How many books did it collect this year?
Options:
a. 832
b. 428
c. 351
d. 72

c. 351

Explanation:
From the given data,
Last year, the number of used books collected by city library by its shelves = 117 books
This year, it collected 3 times as many books = 3 x 117 =351 books
Total number of books collected by the city library for this year = 351 books

Question 4.
Washington Elementary has 232 students. Washington High has 6 times as many students. How many students does Washington High have?
Options:
a. 1,392
b. 1,382
c. 1,292
d. 1,281

a. 1,392

Explanation:
As per the given data,
The number of students in Washington elementary = 232 students
Washington High has 6 times as many students = 6 x 232 = 1392
Total number of students in Washington High = 1392 students

Question 5.
What are the partial products of 35 × 7?
Options:
a. 10, 12
b. 21, 35
c. 210, 35
d. 350, 21

c. 210, 35

Explanation:
Partial products of 35 x 7 are 210, 35

Question 6.
Shelby has ten $5 bills and thirteen$10 bills. How much money does Shelby have in all?
Options:
a. $15 b.$60
c. $63 d.$180

d. $180 Explanation: From the given data, Shelby has ten$5 bills and thirteen $10 bills = (10 x$5) + (13 x $10) = ($50) + ($130) =$180
Total money with Shelby = $180 ### Page No. 169 Question 1. Explain how to find 40 × 50 using mental math. Type below: __________ Answer: 200 Explanation: 40 x 50 By using mental math 4 x 5 = 20 40 x 50 = 200 Question 2. What is the first step in estimating 56 × 27? Type below: __________ Answer: 18 centimeters Explanation: Round to the nearest values. So, the first step of the estimated 56 x 27 is rounding to the nearest values that is 60 x 30 Choose a method. Then find the product. Question 3. 35 × 10 = _____ Answer: 350 Explanation: By using the place value method You can take 10 as 1 ten 35 x 10 = 35 x 1 ten = 35 ten 35 x 10 = 350 Question 4. 19 × 20 = _____ Answer: 380 Explanation: 19 x 20 By using the associative property You can think of 20 as (2 x 10) 19 x 20 = 19 x (2 x 10) = (19 x 2) x 10 = 38 x 10 19 x 20 = 380 Question 5. 12 × 80 = _____ Answer: 960 Explanation: Use the halving and doubling strategy half of the 80 to make the problem simpler 80/ 2 = 40 Multiply 40 with 12 40*12 = 480 Double the 480 2*480= 960 12*80 = 960 Question 6. 70 × 50 = _____ Answer: 3,500 Explanation: 70 x 50 By using the place value method You can take 50 as 5 tens 70 x 50 = 70 x 5 tens = 350 tens 70 x 50 = 3,500 Question 7. 58 × 40 = _____ Answer: 2,320 Explanation: By using the associative property You can think of 40 as (4 x 10) 58 x 40 = 58 x (4 x 10) = (58 x 4) x 10 = 232 x 10 58 x 40 = 2,320 Question 8. 30 × 40 = _____ Answer: 1,200 Explanation: Use the halving and doubling strategy half of the 40 to make the problem simpler 40/ 2 = 20 Multiply 20 with 30 20*30 = 600 Double the 600 2*600= 1200 30*40 = 1,200 Question 9. 14 × 60 = _____ Answer: 840 Explanation: By using the place value method You can take 60 as 6 tens 14 x 60 = 14 x 6 tens = 84 tens 14 x 60 = 840 Question 10. 20 × 30 = _____ Answer: 600 Explanation: By using the associative property You can think of 30 as (3 x 10) 20 x 30 = 20 x (3 x 10) = (20 x 3) x 10 = 60 x 10 20 x 30 = 600 Question 11. 16 × 90 = _____ Answer: 1,440 Explanation: Use the halving and doubling strategy half of the 90 to make the problem simpler 90/ 2 = 45 Multiply 45 with 16 16*45 = 720 Double the 720 2*720= 1440 16*90 = 1,440 Estimate the product. Choose a method. Question 12. 81 × 38 Estimate: _____ Answer: 3,200 Explanation: Round to the nearest tens. 81 is close to 80; 38 is close to 40; 80 x 40 = 3,200 Question 13. 16 ×$59
Estimate: $_____ Answer:$120

Explanation:
Round to the nearest tens.
16 is close to 20; $59 is close to$60;
Use the mental math to find the product of 20 x $60 2 x$6 = $12 20 x$60 = $120 Estimated product of 16 x$59 = $120 Question 14. 43 × 25 Estimate: _____ Answer: 1,000 Explanation: Round to the nearest tens. 43 is close to 40; 25 is close to 25; 40 x 25 = 1000 Estimated product of 43 x 25 = 1,000 Question 15. 76 × 45 Estimate: _____ Answer: 3,200 Explanation: Round to the nearest tens. 76 is close to 80; 45 is close to 40; Use the mental math 8 x 4 = 32 80 x 40 = 3200 So, the estimated product of 76 x 45 = 3,200 Question 16. 65 ×$79
Estimate: _____

$4,800 Explanation: Round to the nearest tens. 65 is close to 60;$79 is close to $80; Use the mental math 6 x$8 = $48 60 x$80 = $4800 So, estimated product of 65 x$79 = $4,800 Question 17. 92 × 38 Estimate: _____ Answer: 3,600 Explanation: Round to the nearest tens. 92 is close to 90; 38 is close to 40; Use the mental math, then 9 x 4 = 36 90 x 40 = 3,600 So, estimated product of 92 x 38 = 3,600 Question 18. 37 × 31 Estimate: _____ Answer: 1,200 Explanation: Round to the nearest tens. 37 is close to 40; 31 is close to 30; Use the mental math, then 4 x 3 = 12 40 x 30 = 1,200 So, estimated product of 37 x 31 = 1,200 Question 19. 26 ×$59
Estimate: _____

$1,800 Explanation: Round to the nearest tens. 26 is close to 30;$59 is close to $60; Use the mental math, then 3 x$6 = $18 30 x$60 = $1,800 So, estimated product of 26 x$59 = $1,800 Question 20. 54 × 26 Estimate: _____ Answer: 18 centimeters Explanation: Round to the nearest tens. 54 is close to 50; 26 is close to 30; Use the mental math 5 x 3 = 15 50 x 30 = 1,500 So, estimated product of 54 x 26 = 1,500 Question 21. 52 × 87 Estimate: _____ Answer: 4,500 Explanation: Round to the nearest tens. 52 is close to 50; 87 is close to 90; Use the mental math 5 x 9 = 45 50 x 90 = 4500 So, estimated product of 52 x 87 = 4,500 Question 22. 39 × 27 Estimate: _____ Answer: 18 centimeters Explanation: Round to the nearest tens. 39 is close to 40; 27 is close to 30; Use the mental math 4 x 3 = 12 40 x 30 = 1,200 So, estimated product of 39 x 27 = 1,200 Question 23. 63 × 58 Estimate: _____ Answer: 3,600 Explanation: Round to the nearest tens. 63 is close to 60; 58 is close to 60; Use the mental math 6 x 6 = 36 60 x 60 = 3,600 So, estimated product of 63 x 58 = 3,600 ### Page No. 170 Question 24. Ms. Traynor’s class is taking a field trip to the zoo. The trip will cost$26 for each student. There are 22 students in her class. What is a good estimate for the cost of the students’ field trip?
Type below:
__________

18 centimeters

Explanation:
As per the given data,
Ms. Traynor’s class is taking a field trip to the zoo
Cost of the trip for each student = $26 Total number of students in her class = 22 The total cost of the trip for students =$26 x 22
Round to the nearest tens.
26 is close to 30; 22 is close to 20;
Use the mental math
$3 x 2 =$6
$30 x 20 =$600
Then, the total estimated cost for the trip for students = $600 Question 25. Tito wrote the following on the board. What is the unknown number? ______ Answer: 400 Explanation: An unknown number is 50 x 8 = 400 Question 26. What are the partial products that result from multiplying 15 × 32? Type below: __________ Answer: Partial products are 300, 150, 20, 10 Explanation: Partial products are 300, 150, 20, 10 Question 27. A city bus company sold 39 one-way tickets and 20 round-trip tickets from West Elmwood to East Elmwood. One-way tickets cost$14. Round trip tickets cost $25. How much money did the bus company collect?$ ______

$1,046 Explanation: As per the given data, Number of one – way tickets sold by the city bus company = 39 Round trip tickets from west Elmwood to east Elmwood = 20 Cost of one – way tickets =$14
Then, cost of 39 one – way tickets = 39 x $14 =$546
Cost of round trip tickets = $25 Then, cost of 20 round trip tickets =$25 x 20 = $500 Total money collected by the city bus company =$546 + $500 =$1,046

### Page No. 173

Question 1.
Look at the problem. Complete the sentences.
Multiply ____ and ____ to get 0.
Multiply ____ and ____ to get 1,620.
0 + 1,620 = ____

_____

Multiply 27 and 0 to get 0.
Multiply 27 and 6 to get 1,620.
Add the partial products. 0 + 1,620 = 1,620.

Estimate. Then find the product.

Question 2.
6 8
× 5 3
——-
Estimate: _________
Product: __________

Estimate: 3,500
Product: 3,604

Explanation:
68 is closer to 70 and 53 is closer to 50
Estimate: 70 x 50 = 3,500
60 x 53 = 3180
8 x 53 = 424
3180 + 424 = 3604
Product 3,604

Question 3.
6 1
× 5 4
——-
Estimate: _________
Product: __________

Estimate: 3,000
Product: 3,294

Explanation:
61 is closer to 60 and 54 is closer to 50
Estimate: 60 x 50 = 3,000
60 x 54 = 3240
1 x 54 = 54
3240 + 54 = 3294
Product 3,294

Question 4.
9 0
× 2 7
——-
Estimate: _________
Product: __________

Estimate: 2,700
Product: 2,430

Explanation:
27 is closer to 30
Estimate: 90 x 30 = 2,700
90 x 27 = 2430
Product 2,430

Question 5.
3 0
× 4 7
——-
Estimate: _________
Product: __________

Estimate: 1,500
Product: 1,410

Explanation:
47 is closer to 50
Estimate: 30 x 50 = 1,500
30 x 47 = 1410
Product 1,410

Question 6.
7 8
× 5 6
——-
Estimate: _________
Product: __________

Estimate: 4,800
Product: 4,368

Explanation:
78 is closer to 80 and 56 is closer to 60
Estimate: 80 x 60 = 4,800
70 x 56 = 3920
8 x 56 = 448
3920 + 448 = 4368
Product 4,368

Question 7.
2 7
× 2 5
——-
Estimate: _________
Product: __________

Estimate: 600
Product: 675

Explanation:
27 is closer to 30 and 25 is closer to 20
Estimate: 30 x 20 = 600
20 x 25 = 500
7 x 25 = 175
500 + 175 = 675
Product 675

Practice: Copy and Solve Estimate. Then find the product.

Question 8.
34 × 65
Estimate: _________
Product: __________

Estimate: 1,800
Product: 2,210

Explanation:
34 is closer to 30 and 65 is closer to 60
Estimate: 30 x 60 = 1,800
30 x 65 = 1950
4 x 65 = 260
1950 + 260 = 2210
Product 2,210

Question 9.
42 × $13 Estimate:$ _________
Product: $_________ Answer: Estimate:$400
Product: $546 Explanation: 42 is closer to 40 and 13 is closer to 10 Estimate: 40 x 10 = 400 40 x$13 = $520 2 x$13= $26$520 + $26 =$546
Product $546 Question 10. 60 × 17 Estimate: _________ Product: __________ Answer: Estimate: 1,200 Product: 1,020 Explanation: 17 is closer to 20 Estimate: 60 x 20 = 1,200 60 x 17 = 1020 Product = 1,020 Question 11. 62 × 45 Estimate: _________ Product: __________ Answer: Estimate: 2,400 Product: 2,790 Explanation: 62 is closer to 60 and 45 is closer to 40 Estimate: 60 x 40 = 2,400 60 x 45 = 2700 2 x 45= 90 2700 + 90 = 2790 Product 2,790 Question 12. 57 ×$98
Estimate: $_________ Product:$ _________

Estimate: 6,000
Product: 5,586

Explanation:
57 is closer to 60 and 98 is closer to 100
Estimate: 60 x 100 = 6,000
50 x 98 = 4900
7 x 98= 686
4900 + 686 = 5586
Product 5,586

Look for a Pattern Algebra Write a rule for the pattern.
Use your rule to find the unknown numbers.

Question 13.

Rule _____________
Type below:
_________

Explanation:
1 hour = 60 min
Then, 5hr = 5 x 60 = 300 min
10hr = 10 x 60 = 600 min
15hr = 15 x 60 = 900 min
20hr = 20 x 60 = 1200 min
25hr = 25 x 60 = 1500 min

Question 14.
Owners of a summer camp are buying new cots for their cabins. There are 16 cabins. Each cabin needs 6 cots. Each cot costs $92. How much will the new cots cost?$ _______

$8,832 Explanation: As per the given data, Owners pf a summer camp are buying new cots for their cabins Number of cabins = 16 Each cabin needs 6 cots Then, total cots = 16 x 6 = 96 Each cot cost =$92
Then, cost for total cots = $92 x 96 92 is closer to 90 and 96 is closer to 100 Estimate = 90 x 100 = 9,000 90 x 96 = 8640 2 x 96 = 192 8640 + 192 = 8832 Product = 8,832 Question 15. A theater has 28 rows of 38 seats downstairs and 14 rows of 26 seats upstairs. How many seats does the theater have? ______ seats Answer: 1,428 seats Explanation: As per the given data, A theatre has 28 rows of 38 seats downstairs = 28 x 38 = 1064 14 rows of 26 seats upstairs = 14 x 26 = 364 Total number of seats = 1064 + 364 = 1,428 seats ### Page No. 174 Question 16. Machine A can label 11 bottles in 1 minute. Machine B can label 12 bottles in 1 minute. How many bottles can both machines label in 15 minutes? a. What do you need to know? Type below: __________ Answer: number of bottles labeled by Machine A and Machine B in 15 minutes Question 16. b. What numbers will you use? Type below: __________ Answer: 15x 11 and 15 x 12 Question 16. c. Tell why you might use more than one operation to solve the problem. Type below: __________ Answer: To find out the total number of bottle made by both machines A & B Question 16. d. Solve the problem. So, both machines can label ____ bottles in ____ minutes. Type below: __________ Answer: Machine A can label 11 bottles in 1 minute Then, the number of bottles labeled by machine A in 15 minutes = 15 x 11 = 165 Machine B can label 12 bottles in 1 minute Then, number of bottles labelled by Machine B in 15 minutes = 15 x 12 = 180 Total bottles labelled by both the machines in 15 minutes = 165 + 180 = 345 Question 17. Make Sense of Problems A toy company makes wooden blocks. A carton holds 85 blocks. How many blocks can 19 cartons hold? ______ blocks Answer: 1,615 blocks Explanation: From the given data, A toy company makes wooden blocks A carton holds 85 blocks Then, number of blocks hold by 19 cartons = 19 x 85 = 1615 Total number of blocks held by 19 cartons = 1,615 Question 18. A company is packing cartons of candles. Each carton can hold 75 candles. So far, 50 cartons have been packed, but only 30 cartons have been loaded on a truck. How many more candles are left to load on the truck? ______ candles Answer: 1,500 candles Explanation: As per the given data, A company is packing cartons of candles Each carton can hold 75 candles Then, number of candles hold by 50 cartons = 50 x 75 = 3750 Number of candles hold by 30 cartons = 30 x 75 = 2250 50 cartons have been packed, but only 30 cartons have been loaded on a truck Remaining candles are left to load on truck = 3750 – 2250 = 1,500 Question 19. Mr. Garcia’s class raised money for a field trip to the zoo. There are 23 students in his class. The cost of the trip will be$17 for each student. What is the cost for all the students? Explain how you found your answer.
$______ Answer:$391

Explanation:
As per the given data,
Mr. Garcia’s class raised money for a field trip to the zoo
Total number of students in his class = 23 students
Cost of the trip for each student = $17 Then, total cost for all the students =$17 x 23 = $391 ### Common Core – Page No. 175 Multiply with Regrouping Estimate. Then find the product. Question 1. Estimate: 2,700 Think: 87 is close to 90 and 32 is close to 30. 90 × 30 = 2,700 Answer: 2,784 Explanation: Think: 87 is close to 90 and 32 is close to 30. 90 × 30 = 2,700 Question 2. 7 3 × 2 8 ——– Estimate: ______ Product: _______ Answer: Estimate: 2,100 Product: 2,044 Explanation: Estimate: 73 is close to 70; 28 is close to 30. So, 70 x 30 = 2,100. Product: Write 73 as 7 tens and 3 ones. Multiply 28 by 3 ones. 2 28 x 73 ——– 84 <– 3 x 28 Multiply 28 by 7 tens 5 28 x 73 ——– 1960 <– 70 x 28 Add the partial products. 84 + 1960 = 2,044. So, 73 x 28 = 2,044. Question 3. 4 8 × 3 8 ——– Estimate: ______ Product: _______ Answer: Estimate: 2,000 Product: 1,824 Explanation: 48 is close to 50 and 38 is close to 40. Estimate: 50 × 40 = 2,000 40 x 38 = 1520 8 x 38 = 304 1520 + 304 = 1824. Product: 1,824 Question 4. 5 9 × 5 2 ——– Estimate: ______ Product: _______ Answer: Estimate: 3,000 Product: 3,068 Explanation: 59 is close to 60 and 52 is close to 50. Estimate: 60 × 50 = 3,000 50 x 52 = 2600 9 x 52 = 468 2600 + 468 = 3068. Product: 3,068. Question 5. 8 4 × 4 0 ——– Estimate: ______ Product: _______ Answer: Estimate: 3,200 Product: 3,360 Explanation: 84 is close to 80 and 40 is close to 40. Estimate: 80 × 40 = 3,200 80 x 40 = 3,200 4 x 40 = 160 3200 + 160 = 3,360. Product: 3,360. Question 6. 8 3 × 7 7 ——– Estimate: ______ Product: _______ Answer: Estimate: 6,400 Product: 6,391 Explanation: 83 is close to 80 and 77 is close to 80. Estimate: 80 × 80 = 6,400 80 x 77 = 6,160 3 x 77 = 231 6,160 + 231 = 6,391. Product: 6,391. Question 7. 9 1 × 1 9 ——– Estimate: ______ Product: _______ Answer: Estimate: 1,800 Product: 1,729 Explanation: 91 is close to 90 and 19 is close to 20. Estimate: 90 × 20 = 1,800 90 x 19 = 1,710 1 x 19 = 19 1,710+ 19 = 1,729. Product: 1,729. Problem Solving Question 8. Baseballs come in cartons of 84 baseballs. A team orders 18 cartons of baseballs. How many baseballs does the team order? _______ baseballs Answer: 1,512 baseballs Explanation: To find total baseballs, 84 x 18 80 x 18 = 1,440 4 x 18 = 72 84 x 18 = 1,512 Question 9. There are 16 tables in the school lunch room. Each table can seat 22 students. How many students can be seated at lunch at one time? _______ students Answer: 352 students Explanation: Total Students = 16 x 22 10 x 22 = 220 6 x 22 = 132 220 + 132 = 352. 352 students can be seated at lunch at one time ### Common Core – Page No. 176 Lesson Check Question 1. The art teacher has 48 boxes of crayons. There are 64 crayons in each box. Which is the best estimate of the number of crayons the art teacher has? Options: a. 2,400 b. 2,800 c. 3,000 d. 3,500 Answer: c. 3,000 Explanation: 1. Total number of crayons = 48 x 64 48 is close to 50; 64 is close to 60 50 x 60 = 3,000. The art teacher has about to 3, 000 crayons. Question 2. A basketball team scored an average of 52 points in each of 15 games. How many points did the team score in all? Options: a. 500 b. 312 c. 780 d. 1,000 Answer: c. 780 Explanation: Total Points = 52 x 15 50 x 15 = 750 2 x 15 = 30 750 + 30 = 780. The basketball team scored 780 points in total. Spiral Review Question 3. One Saturday, an orchard sold 83 bags of apples. There are 27 apples in each bag. Which expression represents the total number of apples sold? Options: a. 16 + 6 + 56 + 21 b. 160 + 60 + 56 + 21 c. 160 + 60 + 560 + 21 d. 1,600 + 60 + 560 + 21 Answer: d. 1,600 + 60 + 560 + 21 Explanation: Total number of apples sold = 83 x 27 80 x 27 = 2,160 3 x 27 = 81 2,160 + 81 = 2,241. The total number of apples sold = 2,241. 16 + 6 + 56 + 21 = 99 not equal to 2,241 160 + 60 + 56 + 21 = 297 not equal to 2,241 160 + 60 + 560 + 21 = 801 not equal to 2,241 1,600 + 60 + 560 + 21 = 2,241 equal to 2,241 1,600 + 60 + 560 + 21 = 2,241 is correct. Question 4. Hannah has a grid of squares that has 12 rows with 15 squares in each row. She colors 5 rows of 8 squares in the middle of the grid blue. She colors the rest of the squares red. How many squares does Hannah color red? Options: a. 40 b. 140 c. 180 d. 220 Answer: b. 140 Explanation: Hannah has a grid of squares that has 12 rows with 15 squares in each row = 12 x 15 = 180. The grid of squares in blue = 5 x 8 = 40. The grid of squares in red = 180 – 40 = 140. Question 5. Gabriella has 4 times as many erasers a Leona. Leona has 8 erasers. How many erasers does Gabriella have? Options: a. 32 b. 24 c. 12 d. 2 Answer: a. 32 Explanation: Gabriella have 4 x 8 = 32 erasers. Question 6. Phil has 3 times as many rocks as Peter. Together, they have 48 rocks. How many more rocks does Phil have than Peter? Options: a. 36 b. 24 c. 16 d. 12 Answer: b. 24 Explanation: Phil has 3 times as many rocks as Peter. Together, they have 48 rocks If Peter has x rocks, Phil has 3x rocks 3x + x = 48. 4x = 48. x = 48/4 = 12. Peter has 12 rocks. Phil has 3 x 12 = 36 rocks. Phil has 36 – 12 = 24 more rocks than Peter. ### Page No. 179 Question 1. Find the product. Estimate: ______ Product: _______ Answer: Estimate: 1,500 Product: 1,566 Explanation: 54 x 29 Estimate: Think 54 is close to 50; 29 is close to 30. 50 x 30 = 1,500 Product: 20 x 5 tens = 100 tens 20 x 4 ones = 80 ones 9 x 5 tens = 45 tens 9 x 4 ones = 36 ones. Add partial products. 1000 + 80 + 450 + 36 = 1,566. Estimate. Then choose a method to find the product. Question 2. 3 6 × 1 4 ——- Estimate: ______ Product: _______ Answer: Estimate: 400 Product: 504 Explanation: 36 x 14 Estimate: Think 36 is close to 40; 14 is close to 10. 40 x 10 = 400 Product: 10 x 3 tens = 30 tens 10 x 6 ones = 60 ones 4 x 3 tens = 12 tens 4 x 6 ones = 24 ones. Add partial products. 300 + 60 + 120 + 24 = 504. Question 3. 6 3 × 4 2 ——- Estimate: ______ Product: _______ Answer: Estimate: 2,400 Product: 2646 Explanation: 63 x 42 Estimate: Think 63 is close to 60; 42 is close to 40. 60 x 40 = 2400 Product: 40 x 6 tens = 240 tens 40 x 3 ones = 120 ones 2 x 6 tens = 12 tens 2 x 3 ones = 6 ones. Add partial products. 2400 + 120 + 120 + 6 = 2646. Question 4. 8 4 × 5 3 ——- Estimate: ______ Product: _______ Answer: Estimate: 4,000 Product: 4,452 Explanation: 84 x 53 Estimate: Think 84 is close to 80; 53 is close to 50. 80 x 50 = 4,000 Product: 50 x 8 tens = 400 tens 50 x 4 ones = 200 ones 3 x 8 tens = 24 tens 3 x 4 ones = 12 ones. Add partial products. 4000 + 200 + 240 + 12 = 4,452. Question 5. 7 1 × 1 3 ——- Estimate: ______ Product: _______ Answer: Estimate: 700 Product: 923 Explanation: 71 x 13 Estimate: Think 71 is close to 70; 13 is close to 10. 70 x 10 = 700 Product: 10 x 7 tens = 70 tens 10 x 1 ones = 10 ones 3 x 7 tens = 21 tens 3 x 1 ones = 3 ones. Add partial products. 700 + 10 + 210 + 3 = 923. Practice: Copy and Solve Estimate. Find the product. Question 6. 29 ×$82
Estimate: $_______ Product:$ _______

Estimate: $2,400 Product:$2,378

Explanation:
29 x $82 Estimate: Think 29 is close to 30;$82 is close to $80. 30 x$80 = $2,400 Product:$80 x 2 tens = $160 tens$80 x 9 ones = $720 ones$2 x 2 tens = $4 tens$2 x 9 ones = $18 ones. Add partial products.$1600 + $720 +$40 + $18 =$2,378.

Question 7.
57 × 79
Estimate: _______
Product: _______

Estimate: 4,800
Product: 4,503

Explanation:
57 x 79
Estimate: Think 57 is close to 60; 79 is close to 80.
60 x 80 = 4,800
Product:
70 x 5 tens = 350 tens
70 x 7 ones = 490 ones
9 x 5 tens = 45 tens
9 x 7 ones = 63 ones.
3500 + 490 + 450 + 63 = 4,503.

Question 8.
80 × 27
Estimate: _______
Product: _______

Estimate: 2,400
Product: 2,160

Explanation:
80 x 27
Estimate: Think 27 is close to 30.
30 x 80 = 2,400
Product:
20 x 8 tens = 160 tens
20 x 0 ones = 0 ones
7 x 8 tens = 56 tens
7 x 0 ones = 0 ones.
1600 + 0 + 560 + 0 = 2,160.

Question 9.
32 × $75 Estimate:$ _______
Product: $_______ Answer: Estimate:$2,100
Product: $2,400 Explanation: 32 ×$75
Estimate: Think 32 is close to 30; $75 is close to$70.
30 x $70 =$2,100
Product:
$70 x 3 tens =$210 tens
$70 x 2 ones =$140 ones
$5 x 3 tens =$15 tens
$5 x 2 ones =$10 ones.
$2100 +$140 + $150 +$10 = $2,400. Question 10. 55 × 48 Estimate: _______ Product: _______ Answer: Estimate: 2,750 Product: 2,640 Explanation: 55 × 48 Estimate: Think 48 is close to 50. 55 x 50 = 2,750 Product: 40 x 5 tens = 200 tens 40 x 5 ones = 200 ones 8 x 5 tens = 40 tens 8 x 5 ones = 40 ones. Add partial products. 2000 + 200 + 400 + 40 = 2,640. Question 11. 19 ×$82
Estimate: $_______ Product:$ _______

Estimate: $1,600 Product:$1,558

Explanation:
19 × $82 Estimate: Think 19 is close to 20;$82 is close to $80. 20 x$80 = $1,600 Product:$80 x 1 tens = $80 tens$80 x 9 ones = $720 ones$2 x 1 tens = $2 tens$2 x 9 ones = $18 ones. Add partial products.$800 + $720 +$20 + $18 =$1,558.

Question 12.
25 × $25 Estimate:$ _______
Product: $_______ Answer: Estimate:$625
Product: $625 Explanation: 25 ×$25
Estimate:
25 x $25 =$625
Product:
$20 x 2 tens =$40 tens
$20 x 5 ones =$100 ones
$5 x 2 tens =$10 tens
$5 x 5 ones =$25 ones.
$400 +$100 + $100 +$25 = $625. Question 13. 41 × 98 Estimate: _______ Product: _______ Answer: Estimate: 4,000 Product: 4,018 Explanation: 41 × 98 Estimate: Think 41 is close to 40; 98 is close to 100. 40 x 100 = 4,000 Product: 90 x 4 tens = 360 tens 90 x 1 ones = 90 ones 8 x 4 tens = 32 tens 8 x 1 ones = 8 ones. Add partial products. 3600 + 90 + 320 + 8 = 4,018. Identify Relationships Algebra Use mental math to find the number. Question 14. 30 × 14 = 420, so 30 × 15 = ______ Answer: 30 × 15 = 450 Explanation: 30 × 15 = 30 + 420 30 × 15 = 450 Question 15. 25 × 12 = 300, so 25 × ______ = 350 Answer: 25 x 14 = 350 Explanation: 25 × 12 = 300 For every next multiplication, the product value is increased by 25. 25 x 13 = 325. 25 x 14 =350. Question 16. The town conservation manager bought 16 maple trees for$26 each. She paid with five $100 bills. How much change will the manager receive? Explain.$ ______

$84 Explanation: The town conservation manager bought 16 maple trees for$26 each = 16 x $26 =$416.
She paid with five $100 bills = 5 x$100 = $500. The manager receive =$500 – $416 =$84.

Question 17.
Each of 25 students in Group A read for 45 minutes. Each of 21 students in Group B read for 48 minutes. Which group read for more minutes? Explain.
_________

Group A read for more minutes than Group B.

Explanation:
Group A read for 25 x 45 = 1125 minutes.
Group B read for 21 x 48 = 1008 minutes.
Group A read for more minutes than Group B.

### Page No. 180

Question 18.
Martin collects stamps. He counted 48 pages in his collector’s album. The first 20 pages each have 35 stamps in 5 rows. The rest of the pages each have 54 stamps. How many stamps does Martin have in his album?

a. What do you need to know?
Type below:
_________

The total stamps in the first 20 pages + The total stamps in the remaining pages.

Question 18.
b. How will you use multiplication to find the number of stamps?
Type below:
_________

The first 20 pages each have 35 stamps in 5 rows.
So, 35 x 5 = 175 stamps.

Question 18.
c. Tell why you might use addition and subtraction to help solve the problem.
Type below:
_________

As mentioned that the number of stamps available in the first 20 pages and the number of stamps available in the rest of the pages. We need to add all pages to get 48 pages stamps.

Question 18.
d. Show the steps to solve the problem.
Type below:
_________

Martin has 48 pages in his collector’s album.
The first 20 pages each have 35 stamps in 5 rows.
So, 35 x 5 = 175 stamps.
The first 20 pages have 175 stamps.
The rest of the pages each have 54 stamps.
So, total stamps = 175 + 54 = 229 stamps.

Question 18.
e. Complete the sentences.
Martin has a total of _____ stamps on the first 20 pages.
There are _____ more pages after the first 20 pages in Martin’s album.
There are _____ stamps on the rest of the pages.
There are _____ stamps in the album.
Type below:
_________

Martin has a total of __175___ stamps on the first 20 pages.
There are __24___ more pages after the first 20 pages in Martin’s album.
There are __54___ stamps on the rest of the pages.
There are ___229__ stamps in the album.

Question 19.
Select the expressions that have the same product as 35 × 17. Mark all that apply.
Options:
a. (30 × 10) + (30 × 7) + (5 × 10) + (5 × 7)
b. (30 × 17) + (5 × 17)
c. (35 × 30) + (35 × 5) + (35 × 10) + (35 × 7)
d. (35 × 10) + (35 × 7)
e. (35 × 10) + (30 × 10) + (5 × 10) + (5 × 7)
f. (35 × 30) + (35 × 5)

a. (30 × 10) + (30 × 7) + (5 × 10) + (5 × 7)
b. (30 × 17) + (5 × 17)
d. (35 × 10) + (35 × 7)

Explanation:
35 × 17
30 x 10 =300
30 x 7 = 210
5 x 10 = 50
5 x 7 = 35
300 + 210 + 50 + 35 = 595.
a. (30 × 10) + (30 × 7) + (5 × 10) + (5 × 7) = 300 + 210 + 50 + 35 = 595 equal to 595.
b. (30 × 17) + (5 × 17) = 510 + 85 = 595 equal to 595.
c. (35 × 30) + (35 × 5) + (35 × 10) + (35 × 7) = 1050 + 175 + 350 + 245 = 1820 not equal to 595.
d. (35 × 10) + (35 × 7) = 350 + 245 = 595 equal to 595
e. (35 × 10) + (30 × 10) + (5 × 10) + (5 × 7) = 350 + 300 + 50 + 35 = 735 not equal to 595.
f. (35 × 30) + (35 × 5) = 1050 + 175 = 1,225 not equal to 595.

### Common Core – Page No. 181

Choose a Multiplication Method

Estimate. Then choose a method to find the product.

Question 1.
Estimate: 1,200
3 1
× 4 3
——-
9 3
+ 1, 2 4 0
————
1, 3 3 3

Estimate: 1,200
Product: 1, 3 3 3

Explanation:
Estimate: 1,200
3 1
× 4 3
——-
9 3
+ 1, 2 4 0
————
1, 3 3 3

Question 2.
6 7
× 8 5
——-
Estimate: _____
Product: ______

Estimate: 6,300
Product: 5,695

Explanation:
Estimate: 67 is close to 70; 85 is close to 90.
70 x 90 = 6,300.
Product: 67 x 85
80 x 6 tens = 480 tens
80 x 7 ones = 560 ones
5 x 6 tens = 30 tens
5 x 7 ones = 35 ones.
4800 + 560 + 300 + 35 = 5,695.

Question 3.
6 8
× 3 8
——-
Estimate: _____
Product: ______

Estimate: 2,800
Product: 2,584

Explanation:
Estimate: 68 is close to 70; 38 is close to 40.
70 x 40 = 2,800.
Product: 68 x 38
30 x 6 tens = 180 tens
30 x 8 ones = 240 ones
8 x 6 tens = 48 tens
8 x 8 ones = 64 ones.
1800 + 240 + 480 + 64 = 2,584.

Question 4.
9 5
× 1 7
——-
Estimate: _____
Product: ______

Estimate: 1,700
Product: 1,615

Explanation:
Estimate: 95 is close to 100.
100 x 17 = 1,700.
Product: 95 x 17
10 x 9 tens = 90 tens
10 x 5 ones = 50 ones
7 x 9 tens = 63 tens
7 x 5 ones = 35 ones.
900 + 50 + 630 + 35 = 1,615.

Question 5.
4 9
× 5 4
——-
Estimate: _____
Product: ______

Estimate: 2,500
Product: 2,646

Explanation:
Estimate: 49 is close to 50; 54 is close to 50.
50 x 50 = 2,500.
Product: 49 x 54
50 x 4 tens = 200 tens
50 x 9 ones = 450 ones
4 x 4 tens = 16 tens
4 x 9 ones = 36 ones.
2000 + 450 + 160 + 36 = 2,646.

Question 6.
9 1
× 2 6
——-
Estimate: _____
Product: ______

Estimate: 2,700
Product: 2,366

Explanation:
Estimate: 91 is close to 90; 26 is close to 30.
90 x 30 = 2,700.
Product: 49 x 54
20 x 9 tens = 180 tens
20 x 1 ones = 20 ones
6 x 9 tens = 54 tens
6 x 1 ones = 6 ones.
1800 + 20 + 540 + 6 = 2,366.

Question 7.
8 2
× 1 9
——-
Estimate: _____
Product: ______

Estimate: 1,600
Product: 1,558

Explanation:
Estimate: 82 is close to 80; 19 is close to 20.
80 x 20 = 1,600.
Product: 82 x 19
10 x 8 tens = 80 tens
10 x 2 ones = 20 ones
9 x 8 tens = 72 tens
9 x 2 ones = 18 ones.
800 + 20 + 720 + 18 = 1,558.

Question 8.
4 6
× 2 7
——-
Estimate: _____
Product: ______

Estimate: 1,500
Product: 1,242

Explanation:
Estimate: 46 is close to 50; 27 is close to 30.
50 x 30 = 1,500.
Product: 46 x 27
20 x 4 tens = 80 tens
20 x 6 ones = 120 ones
7 x 4 tens = 28 tens
7 x 6 ones = 42 ones.
800 + 120 + 280 + 42 = 1,242.

Question 9.
4 1
× 3 3
——-
Estimate: _____
Product: ______

Estimate: 1,200
Product: 1,353

Explanation:
Estimate: 41 is close to 40; 33 is close to 30.
40 x 30 = 1,200.
Product: 41 x 33
30 x 4 tens = 120 tens
30 x 1 ones = 30 ones
3 x 4 tens = 12 tens
3 x 1 ones = 3 ones.
1200 + 30 + 120 + 3 = 1,353.

Question 10.
9 7
× 1 3
——-
Estimate: _____
Product: ______

Estimate: 1,300
Product: 1,261

Explanation:
Estimate: 97 is close to 100.
100 x 13 = 1,300.
Product: 97 x 13
10 x 9 tens = 90 tens
10 x 7 ones = 70 ones
3 x 9 tens = 27 tens
3 x 7 ones = 21 ones.
900 + 70 + 270 + 21 = 1,261.

Question 11.
7 5
× 6 9
——-
Estimate: _____
Product: ______

Estimate: 5,600
Product: 5,195

Explanation:
Estimate: 75 is close to 80; 69 is close to 70.
80 x 70 = 5,600.
Product: 75 x 69
60 x 7 tens = 420 tens
60 x 5 ones = 300 ones
9 x 7 tens = 63 tens
9 x 5 ones = 45 ones.
4200 + 300 + 630 + 45 = 5,195.

Problem Solving

Question 12.
A movie theatre has 26 rows of seats. There are 18 seats in each row. How many seats are there in all?
______ seats

468 seats

Explanation:
26 x 18 = 468 seats.
20 x 18 = 360
6 x 18 = 108
108+360 = 468.

Question 13.
Each class at Briarwood Elementary collected at least 54 cans of food during the food drive. If there are 29 classes in the school, what was the least number of
cans collected?
______ cans

1,566 cans

Explanation:
Each class at Briarwood Elementary collected at least 54 cans of food.
If there are 29 classes in the school,
the least number of cans collected = 54 x 29 = 1,566 cans.

### Common Core – Page No. 182

Lesson Check

Question 1.
A choir needs new robes for each of its 46 singers. Each robe costs $32. What will be the total cost for all 46 robes? Options: a.$1,472
b. $1,372 c.$1,362
d. $230 Answer: a.$1,472

Explanation:
46 x $32 40 x$32 = $1,280 6 x$32 = $192$1,280 + $192 =$1,472

Question 2.
A wall on the side of a building is made up of 52 rows of bricks with 44 bricks in each row. How many bricks make up the wall?
Options:
a. 3,080
b. 2,288
c. 488
d. 416

b. 2,288

Explanation:
52 x 44
50 x 44 = 2,200
2 x 44 = 88
2,200 + 88 = 2,288.
2,288 bricks make up the wall.

Spiral Review

Question 3.
Which expression shows how to multiply 4 × 362 by using place value and expanded form?
Options:
a. (4 × 3) + (4 × 6) + (4 × 2)
b. (4 × 300) + (4 × 600) +(4 × 200)
c. (4 × 300) + (4 × 60) + (4 × 20)
d. (4 × 300) + (4 × 60) + (4 × 2)

d. (4 × 300) + (4 × 60) + (4 × 2)

Explanation:
4 × 362 = 1,448
a. (4 × 3) + (4 × 6) + (4 × 2) = 12 + 24 + 8 = 44 not equal to 1,448.
b. (4 × 300) + (4 × 600) +(4 × 200) = 1200 + 2400 + 800 = 4,400 not equal to 1,448.
c. (4 × 300) + (4 × 60) + (4 × 20) = 1200 + 240 + 80 = 1,520 not equal to 1,448.
d. (4 × 300) + (4 × 60) + (4 × 2) = 1200 + 240 + 8 = 1,448 equal to 1,448.

Question 4.
Use the model below. What is the product 4 x 492?

Options:
a. 16 + 36 + 8 = 60
b. 160 + 36 + 8 = 204
c. 160 + 360 + 8 = 528
d. 1,600 + 360 + 8 = 1,968

d. 1,600 + 360 + 8 = 1,968

Explanation:

1,600 + 360 + 8 = 1,968

Question 5.
What is the sum 13,094 + 259,728?
Options:
a. 272,832
b. 272,822
c. 262,722
d. 262,712

c. 262,722

Explanation:
13,094 + 259,728 = 262,722

Question 6.
During the 2008–2009 season, there were 801,372 people who attended the home hockey games in Philadelphia. There were 609,907 people who attended the home hockey games in Phoenix. How much greater was the home attendance in Philadelphia than in Phoenix that season?
Options:
a. 101,475
b. 191,465
c. 201,465
d. 202,465

b. 191,465

Explanation:
801,372 – 609,907 = 191,465
Philadelphia attendance is 191,465 greater than in Phoenix that season.

### Page No. 185

Question 1.
An average of 74 reports with bird counts were turned in each day in June. An average of 89 were turned in each day in July. How many reports were turned in for both months? (Hint: There are 30 days in June and 31 days in July.)
First, write the problem for June.
Type below:
__________

Given that An average of 74 reports with bird counts was turned in each day in June.
For June Month, there are 30 days = 30 x 74 = 2,220.

Question 1.
Next, write the problem for July.
Type below:
__________

An average of 89 reports with bird counts was turned in each day in July.
For July Month, there are 31 days = 31 x 89 = 2,759.

Question 1.
Last, find and add the two products.
____________ reports were turned in for both months.
Type below:
__________

Given that An average of 74 reports with bird counts was turned in each day in June.
For June Month, there are 30 days = 30 x 74 = 2,220.
An average of 89 reports with bird counts was turned in each day in July.
For July Month, there are 31 days = 31 x 89 = 2,759.
Add two products to get the total number of reports that were turned in for both months.
2,220 + 2,759 = 4,979.

Question 2.
What if an average of 98 reports were turned in each day for the month of June? How many reports were turned in for June? Describe how your answer for June would be different.
______ reports

720 more reports

Explanation:
Given that an average of 98 reports was turned in each day for the month of June.
June has 30 days.
Total number of reports were turned in for June = 30 x 98 = 2, 940.
From the above answer, 98 − 74 = 24. So, there would be 30 × 24, or 720 more reports.

Question 3.
There are 48 crayons in a box. There are 12 boxes in a carton. Mr. Johnson ordered 6 cartons of crayons for the school. How many crayons did he get?
______ crayons

3,456 crayons

Explanation:
There are 48 crayons in a box.
There are 12 boxes in a carton.
So, 1 carton = 48 x 12 = 576 crayons.
If Mr. Johnson ordered 6 cartons of crayons for the school, 6 x 576 crayons = 3,456 crayons.
He gets 3,456 crayons.

Question 4.
Make Sense of Problems Each of 5 birdwatchers reported seeing 15 roseate spoonbills in a day. If they each reported seeing the same number of roseate spoonbills over 14 days, how many would be reported?
______ roseate spoonbills

1,050 roseate spoonbills

Explanation:
Given that, 1 day –>5 birdwatchers reported 15 roseate spoonbills = 5 x 15 = 75 roseate spoonbills.
So, in 14 days –> 5 birdwatchers reported 75 x 14 = 1,050 roseate spoonbills.

### Page No. 186

Question 5.
On each of Maggie’s bird-watching trips, she has seen at least 24 birds. If she has taken 4 of these trips each year over the past 16 years, at least how many birds has Maggie seen?
at least ______ birds

Maggie seen 1,536 birds

Explanation:
Given that, 1 trip –> Maggie seen 24 birds.
For 1 year she goes for 4 bird-watching trips.
So, she has seen 4 x 24 = 96 birds for 1 year.
For 16 years, 16 x 96 = 1,536 birds have Maggie seen.

Question 6.
Make Sense of Problems There are 12 inches in a foot. In September, Mrs. Harris orders 32 feet of ribbon for the Crafts Club. In January, she orders 9 feet less. How many inches of ribbon does Mrs. Harris order? Explain how you found your answer.
______ inches

660 inches

Explanation:
There are 12 inches in a foot.
In September, Mrs. Harris orders 32 feet of ribbon for the Crafts Club = 32 x 12 = 384.
In January, she orders 9 feet less = 32 – 9 = 23.
So, in January, she orders 23 x 12 = 276.
Mrs. Harris order 276 + 384 = 660 inches of ribbon in total.
(or)
9 less than 32 is 23, so I added 23 + 32 = 55.
Then, I multiplied 55 × 12 = 660.

Question 7.
Lydia is having a party on Saturday. She decides to write a riddle on her invitations to describe her house number on Cypress Street. Use the clues to find Lydia’s address.

______ Cypress Street

14827 Cypress Street

Explanation:
Given that tens digit is 5 less than 7 = 7 – 5 = 2. 2 is the tens digit.
The thousands digit is twice the digit in the tens place = 2 x 2 = 4.
The hundreds digit is the greatest even number that is less than 10 i.e, 8.
The ones digit is the product of 7 and 1 = 7 x 1 = 7.
The ten thousands digit is the difference between the hundreds digit and the ones digit. So, 8 – 7 = 1.
Lydia’s address ( house number ) is 14827 Cypress Street.

Question 8.
A school is adding 4 rows of seats to the auditorium. There are 7 seats in each row. Each new seat costs $99. What is the total cost for the new seats? Show your work.$ ______

$2,772 Explanation: Given that A school is adding 4 rows of seats to the auditorium. There are 7 seats in each row. So, 7 x 4 = 28 seats are available in an auditorium. Each new seat costs$99.
28 x $99 =$2,772 for total cost of the new seats.

### Common Core – Page No. 187

Problem Solving Multiply 2 – Digit numbers

Solve each problem. Use a bar model to help.

Question 1.
Mason counted an average of 18 birds at his bird feeder each day for 20 days. Gloria counted an average of 21 birds at her bird feeder each day for 16 days. How many more birds did Mason count at his feeder than Gloria counted at hers?

Birds counted by Mason: 18 × 20 = 360
Birds counted by Gloria: 21 × 16 = 336
Draw a bar model to compare.
Subtract. 360 – 336 = 24
So, Mason counted 24 more birds.

Birds counted by Mason: 18 × 20 = 360
Birds counted by Gloria: 21 × 16 = 336
Draw a bar model to compare.

Subtract. 360 – 336 = 24
So, Mason counted 24 more birds.

Question 2.
The 24 students in Ms. Lee’s class each collected an average of 18 cans for recycling. The 21 students in Mr. Galvez’s class each collected an average of 25 cans for recycling. How many more cans were collected by Mr. Galvez’s class than Ms. Lee’s class?
______ more cans

The number of cans collected by Ms. Lee’s class = 18 x 24 = 432.
The number of cans collected by Mr. Galvez’s class = 25 x 21 = 525.
Use Bar Model

Subtract. 525 – 432 = 93 more cans.
So, Mr. Galvez’s class collected 93 more cans than Ms. Lee’s class.

Question 3.
At East School, each of the 45 classrooms has an average of 22 students. At West School, each of the 42 classrooms has an average of 23 students. How many more students are at East School than at West School?
______ more students

Students in East school = 45 x 22 = 990.
Students in West School = 42 x 23 = 966.
Use Bar Model

Subtract. 990 – 966 = 24.
So, East School has 24 students more than West School.

Question 4.
A zoo gift shop orders 18 boxes of 75 key rings each and 15 boxes of 80 refrigerator magnets each. How many more key rings than refrigerator magnets does the gift shop order?
______ more key rings

Number of Key Rings = 75 x 18 = 1,350.
Number of Refrigerator Magnets= 80 x 15 = 1,200.
Use Bar Model

Subtract. 1,350 – 1,200 = 150.
So, key rings are 150 more than refrigerator magnets.

### Common Core – Page No. 188

Lesson Check

Question 1.
Ace Manufacturing ordered 17 boxes with 85 ball bearings each. They also ordered 15 boxes with 90 springs each. How many more ball bearings than springs did they order?
Options:
a. 5
b. 85
c. 90
d. 95

d. 95

Explanation:
Number of ball bearings = 85 x 17 = 1,445.
Number of springs = 90 x 15 = 1,350.
Use Bar Model

Subtract. 1,445 – 1,350 = 95.
So, ball bearings are 95 more than springs.

Question 2.
Elton hiked 16 miles each day on a 12-day hiking trip. Lola hiked 14 miles each day on her 16-day hiking trip. In all, how many more miles did Lola hike than Elton hiked?
Options:
a. 2 miles
b. 18 miles
c. 32 miles
d. 118 miles

c. 32 miles

Explanation:
Hiking trip by Elton = 12 x 16 = 192.
Hiking trip by Lola = 16 x 14 = 224.
Use Bar Model

Subtract. 224 – 192 = 32.
So, the Hiking trip by Lola is 32 times more than the Hiking trip by Elton.

Spiral Review

Question 3.
An orchard has 24 rows of apple trees. There are 35 apple trees in each row. How many apple trees are in the orchard?
Options:
a. 59
b. 192
c. 740
d. 840

d. 840

Explanation:
An orchard has 24 rows of apple trees. There are 35 apple trees in each row.
24 x 35 = 840 apple trees are in the orchard.

Question 4.
An amusement park reported 354,605 visitors last summer. What is this number rounded to the nearest thousand?
Options:
a. 354,600
b. 355,000
c. 360,000
d. 400,000

b. 355,000

Explanation:
An amusement park reported 354,605 visitors last summer. 4,605 is close to 5,000. So, the answer is 355,000.

Question 5.
Attendance at the football game was 102,653. What is the value of the digit 6?
Options:
a. 6
b. 60
c. 600
d. 6,000

c. 600

Explanation:
Digit 6 is at hundreds of positions. So, the answer is 6 x 100 = 600.

Question 6.
Jill’s fish weighs 8 times as much as her parakeet. Together, the pets weigh 63 ounces. How much does the fish weigh?
Options:
a. 7 ounces
b. 49 ounces
c. 55 ounces
d. 56 ounces

d. 56 ounces

Explanation:
Let Jill’s parakeet = X.
Jill’s fish weighs 8 times as much as her parakeet = 8X.
Together, the pets weigh 63 ounces.
X + 8X = 63.
9X = 63.
X = 63/9 = 7.
So, Jill’s parakeet =7.
Jill’s fish = 7 x 8 = 56 ounces.

### Review/Test – Page No. 189

Question 1.
Explain how to find 40 × 50 using mental math
Type below:
_________

200

Explanation:
40 x 50
By using mental math
4 x 5 = 20
40 x 50 = 200

Mrs. Traynor’s class is taking a field trip to the zoo. The trip will cost $26 for each student. There are 22 students in her class. Question 2. Part A Round each factor to estimate the total cost of the students’ field trip.$ ______

$600 Explanation: Total cost of the students’ field trip = 22 x$26.
22 x $26 20 x$30 = $600 The total cost would be about$600.

Question 2.
Part B
Use compatible numbers to estimate the total cost of the field trip.
$______ Answer:$500

Explanation:
If we use compatible numbers to estimate the total cost of the field trip.
22 x $26 20 × 25 = 500 The total cost would be about$500.

Question 2.
Part C
Which do you think is the better estimate? Explain.
Better estimate: _________

Using rounded numbers is a better estimate. When rounded numbers are used, one estimated factor was $4 more than the actual factor and the other estimated factor was$2 that is less than the actual factor. So, the estimate should be close to the actual one. When compatible numbers are used both estimated factors were less than the actual factors. So, the product will be an underestimate.

### Review/Test – Page No. 190

For numbers 3a–3e, select Yes or No to show if the answer is correct.

Question 3.
3a. 35 × 10 = 350
i. yes
ii. no

i. yes

Explanation:
35 x 10 = 350
30 x 10 = 300.
5 x 10 = 50.
300 + 50 = 350.

Question 3.
3b. 19 × 20 = 380
i. yes
ii. no

i. yes

Explanation:
19 × 20 = 380
19 x 20 = 19 x 2 tens.
19 x 20 = 38 tens = 380.

Question 3.
3c. 12 × 100 = 120
i. yes
ii. no

ii. no

Explanation:
12 x 100 = 120.
10 x 100 = 1000
2 x 100 = 200.
1000 + 200 = 1200.

Question 3.
3d. 70 × 100 = 7,000
i. yes
ii. no

i. yes

Explanation:
70 x 100 = 7,000
100 x 7 tens = 700 tens = 7,000

Question 3.
3e. 28 × 30 = 2,100
i. yes
ii. no

ii. no

Explanation:
28 × 30
20 x 30 = 600
8 x 30 = 240
600 + 240 = 840

Question 4.
There are 23 boxes of pencils in Mr. Shaw’s supply cabinet. Each box contains 100 pencils. How many pencils are in the supply cabinet?
_____ penciles

2,300 pencils

Explanation:
23 x 100 = 2,300 pencils are in the supply cabinet.

Question 5.
Which would provide a reasonable estimate for each product? Write the estimate beside the product. An estimate may be used more than once
23 × 38 __________
31 × 32 __________
46 × 18 __________
39 × 21 __________

23 × 38 –> 25 x 40
31 x 32 –> 30 × 30
46 × 18 –> 50 × 20
39 × 21 –> 25 × 40

Explanation:
23 × 38; 23 is close to 25; 38 is close to 40.
So, the estimated product is 25 x 40
31 x 32; 31 is close to 30; 32is close to 30.
So, the estimated product is 30 × 30
46 × 18; 46 is close to 50; 18 is close to 20.
So, the estimated product is 50 × 20
39 × 21; 39 is close to 40; 21 is close to 25.
So, the estimated product is 25 × 40

Question 6.
There are 26 baseball teams in the league. Each team has 18 players. Write a number sentence that will provide a reasonable estimate for the number of players in the league. Explain how you found your estimate.
Type below:
__________

There are 26 baseball teams in the league. Each team has 18 players.
26 x 18
25 x 20
We Rounded each factor to its close factor, then simplified the multiplication.

Question 7.
The model shows 48 × 37. Write the partial products.

Type below:
__________

Partial Products are 1200, 240, 280, 56

### Review/Test – Page No. 191

Question 8.
Jess made this model to find the product 32 × 17. Her modelis incorrect.

Part A
What did Jess do wrong?
Type below:
__________

Question 8.
Part B
Redraw the model so that it is correct.

Type below:
__________

Question 8.
Part C
What is the actual product 32 × 17?
______

544

Explanation:
32 × 17
10 x 32 = 320
7 x 32 = 224
320 + 224 = 544.

Question 9.
Tatum wants to use partial products to find 15 × 32. Write the numbers in the boxes to show 15 × 32.

Type below:
__________

### Review/Test – Page No. 192

Question 10.
Which product is shown by the model? Write the letter of the product on the line below the model.

Type below:
__________

C                                              A                                                  B
10 + 3 = 13
10 + 3 = 13
13 x 13
2. 10 + 7 = 17
30 + 6 = 36
17 x 36
3. 20 + 4 = 24
10 + 4 = 14
24 x 14

Question 11.
Mrs. Jones places 3 orders for school T-shirts. Each order has 16 boxes of shirts and each box holds 17 shirts. How many T-shirts does Mrs. Jones order? Use partial products to help you.
Type below:
__________

816 T-shirts

Explanation:
Mrs. Jones places 3 orders for school T-shirts. Each order has 16 boxes of shirts and each box holds 17 shirts.
Each box has 17 shirts.
16 boxes = 16 x 17 = 272.
Each order = 16 boxes = 272 shirts.
3 orders = 3 x 272 = 816 shirts.
Mrs. Jones order 816 T-shirts.

Question 12.
Write the unknown digits. Use each digit exactly once.

Type below:
__________

90 x 40 = 3,600
90 x 6 = 540
3 x 40 = 120
3 x 6 = 18.
3,600 + 540 + 120 + 8 = 4,278.

Question 13.
Mike has 16 baseball cards. Niko has 17 times as many baseball cards as Mike does. How many baseball cards does Niko have?
________ baseball cards

272 baseball cards

Explanation:
Mike has 16 baseball cards. Niko has 17 times as many baseball cards as Mike does.
Niko have 16 x 17 = 272 baseball cards.

Question 14.
Multiply.
36 × 28 = ________

1,008

Explanation:
36 x 28
20 x 30 = 600
20 x 6 = 120
8 x 30 = 240
8 x 6 = 48
600 + 120 + 240 + 48 = 1,008

### Review/Test – Page No. 193

Question 15.
A farmer planted 42 rows of tomatoes with 13 plants in each row. How many tomato plants did the farmer grow?
42 × 13 = ______ tomato plants

420 + 126 = 546 tomato plants

Explanation:
42 × 13
10 x 42 = 420
3 x 42 = 126
420 + 126 = 546 tomato plants

Question 16.
Select another way to show 25 × 18. Mark all that apply.
Options:
a. (20 × 10) + (20 × 8) + (5 × 10) + (5 × 8)
b. (25 × 20) + (25 × 5) + (25 × 10) + (25 × 8)
c. (20 × 18) + (5 × 10) + (5 × 8)
d. (25 × 10) + (25 × 8)
e. (25 × 20) + (25 × 5)

a. (20 × 10) + (20 × 8) + (5 × 10) + (5 × 8)
c. (20 × 18) + (5 × 10) + (5 × 8)
d. (25 × 10) + (25 × 8)

Explanation:
25 × 18
10 x 25 = 250
8 x 25 = 200
250 + 200 = 450.
a. (20 × 10) + (20 × 8) + (5 × 10) + (5 × 8) = 200 + 160 + 50 + 40 = 450
b. (25 × 20) + (25 × 5) + (25 × 10) + (25 × 8) = 500 + 125 + 250 + 200 = 1,075
c. (20 × 18) + (5 × 10) + (5 × 8) = 360 + 50 + 40 = 450
d. (25 × 10) + (25 × 8) = 250 + 200 = 450
e. (25 × 20) + (25 × 5) = 500 + 125 = 625

Question 17.
Terrell runs 15 sprints. Each sprint is 65 meters. How many meters does Terrell run? Show your work.
______ meters

975 meters

Explanation:
Terrell run 15 x 65 = 975 meters.

Question 18.
There are 3 new seats in each row in a school auditorium. There are 15 rows in the auditorium. Each new seat cost $74. What is the cost for the new seats? Explain how you found your answer.$ ______

$3,330 Explanation: Given that There are 3 new seats in each row in a school auditorium. There are 15 rows in the auditorium. Each new seat cost$74.
So, 3 x 15 = 45 seats are available in an auditorium.
Each new seat costs $74. 45 x$74 = $3,330 for total cost of the new seats. Question 19. Ray and Ella helped move their school library to a new building. Ray packed 27 boxes with 25 books in each box. Ella packed 23 boxes with 30 books in each box. How many more books did Ella pack? Show your work. ______ books Answer: 15 books Explanation: Ray packed 27 x 25 = 675 books. Ella packed 23 x 30 = 690 books Ella packed 690 – 675 = 15 books more than Ray. ### Review/Test – Page No. 194 Question 20. Julius and Walt are finding the product of 25 and 16. Part A Julius’ answer is incorrect. What did Julius do wrong? Type below: __________ Answer: Julius multiplied 25 by 10 and then multiplied 25 by 6 correctly. He added the two partial products incorrectly. Question 20. Part B What did Walt do wrong? Type below: __________ Answer: Walt multiplied 6 by 5 and got 300 instead of 30 Question 20. Part C What is the correct product? Type below: __________ Answer: 25 x 16 = 400 Question 21. A clothing store sells 26 shirts and 22 pairs of jeans. Each item of clothing costs$32.
Part A
What is a reasonable estimate for the total cost of the clothing?
$______ Answer:$1500

Explanation:
A clothing store sells 26 shirts and 22 pairs of jeans. 26 + 22 = 48 clothes.
Each item of clothing costs $32. 48 x$32
50 x $30 =$1500

Question 21.
Part B
What is the exact answer for the total cost of the clothing? Show or explain how you found your answer.
$______ Answer:$1,536

Explanation:
48 x $32 40 x$32 = $1,280 8 x$32 = $256$1,280 + $256 =$1,536

### Page No. 199

Question 1.
A restaurant has 68 chairs. There are six chairs at each table. About how many tables are in the restaurant?
Estimate. 68 ÷ 6
Think: What number times 6 is about 68?
10 × 6 = ___
11 × 6 = ___
12 × 6 = ___
68 is closest to ______, so the best estimate is about _______ tables are in the restaurant.
Type below:
__________

68 is close to 70 and 6 is close to 5.
So, 70/5 = 12.
10 × 6 = __60_
11 × 6 = _66__
12 × 6 = _72__
68 is closest to ___66___, so the best estimate is about 11 x 6 = 66 tables are in the restaurant.

Find two numbers the quotient is between. Then estimate the quotient.

Question 2.
41 ÷ 3
between _______ and _______

between 13 and 14

Explanation:
13 x 3 = 39; 14 x 3 = 42.
The quotient of 41 ÷ 3 is between 13 and 14.

Question 3.
192 ÷ 5
between _______ and _______

between 30 and 40

Explanation:
30 x 5 = 150; 40 x 5 = 200.
The quotient of 192 ÷ 5 is between 30 and 40.

Find two numbers the quotient is between. Then estimate the quotient.

Question 4.
90 ÷ 7
between _______ and _______

between 12 and 13

Explanation:
12 x 7 = 84; 13 x 7 = 91.
The quotient of 90 ÷ 7 is between 12 and 13.

Question 5.
67 ÷ 4
between _______ and _______

between 16 and 17

Explanation:
16 x 4 = 64; 17 x 4 = 68.
The quotient of 67 ÷ 4 is between 16 and 17.

Question 6.
281 ÷ 9
between _______ and _______

between 30 and 40

Explanation:
30 x 9 = 270; 40 x 9 = 360.
The quotient of 281 ÷ 9 is between 30 and 40.

Question 7.
102 ÷ 7
between _______ and _______

between 14 and 15

Explanation:
14 x 7 = 98; 15 x 7 = 105.
The quotient of 102 ÷ 7 is between 14 and 15.

Question 8.
85 ÷ 6
between _______ and _______

between 14 and 15

Explanation:
14 x 6 = 84; 15 x 6 = 90.
The quotient of 85 ÷ 6 is between 14 and 15.

Question 9.
220 ÷ 8
between _______ and _______

between 20 and 30

Explanation:
20 x 8 = 160; 30 x 8 = 240.
The quotient of 220 ÷ 8 is between 20 and 30.

Decide whether the actual quotient is greater than or less than the estimate given. Write < or >.

Question 10.
83 ÷ 8 _______ 10

>

Explanation:
83 ÷ 8 = 10.375 > 10

Question 11.
155 ÷ 4 _______ 40

<

Explanation:
155 ÷ 4 = 38.75 < 40

Question 12.
70 ÷ 6 _______ 11

>

Explanation:
70 ÷ 6 = 11.666 > 11

Question 13.
What’s the Question? A dolphin’s heart beats 688 times in 6 minutes. Answer: about 100 times.
Type below:
__________

About how many times does a dolphin’s heart beats in 1 minute?

Question 14.
Analyze A mother bottlenose ate about 278 pounds of food in one week. About how much food did she eat in a day?

Explanation:
278 ÷ 7
The quotient of 278 ÷ 7 is between 39 and 40.

Question 15.
Tanya has $42 to spend at the Dolphin Island store. T-shirts sell for$7 each and a pair of sunglasses sells for $6. Tanya buys 3 T-shirts. How many pairs of sunglasses can she buy with the amount of money she has left? _____ pairs of sunglasses Answer: 3 pairs of sunglasses Explanation: Given that Tanya has$42 to spend at the Dolphin Island store. T-shirts sell for $7 each and a pair of sunglasses sell for$6.
Tanya buys 3 T-shirts = 3 x $7 =$21.
pair of sunglasses = $42 –$21 = $21. 1 pair of sunglasses sells for$6.
So, $21 ÷$7 = 3.
3 pairs of sunglasses can Tanya buy with the amount of money she has left.

### Page No. 200

Question 16.
If a bottlenose dolphin can eat 175 pounds of fish, squid, and shrimp in a week, about how many pounds of food does it eat in a day? Milo says the answer is about 20 pounds. Leah says the answer is about 30 pounds. Who is correct? Explain.

________

The bottlenose dolphin can eat 25 pounds for 1 day.
Both answers are correct. Because the 25 pounds is in between 20 and 30 pounds.

Explanation:
1 week = 7 days.
The bottlenose dolphin can eat 175 pounds for 7 days.
For 1 day = 175 ÷ 7 = 25 pounds.
The bottlenose dolphin can eat 25 pounds for 1 day.
Both answers are correct. Because the 25 pounds is in between 20 and 30 pounds.

Question 17.
Four families went out for lunch. The total food bill came to $167. The families also left a$30 tip for the waitress. If each family spent the same amount, about how much did each family spend on dinner? Explain how you found your answer.
$______ Answer:$98.5

Explanation:
Four families went out for lunch. The total food bill came to $167. The families also left a$30 tip for the waitress.
So, total amount = $167 +$30 = $197. If each family spent the same amount =$197 ÷ 2 = $98.5 Each family spent$98.5.

Question 18.
There are 6 showings of a film about Van Gogh at the Art Museum. A total of 459 people saw the film. The same number of people were at each showing. About how many people were at each showing? Circle the numbers the quotient is between. Then explain how you found your answer.
40 50 60 70 80
Type below:
_________