## Big Ideas Math Book 2nd Grade Answer Key Chapter 3 Addition to 100 Strategies

### Addition to 100 Strategies Vocabulary

**Organize It**

Use the review words to complete the graphic organizer.

Answer :

**Define It**

Use your vocabulary cards to identify the words.

Question 1.

Answer :

Question 2.

Answer :

**Chapter 3 Vocabulary cards**

Answer :

### Lesson 3.1 Add Tens Using a Number Line

**Explore and Grow**

Color and show how you can use the hundred chart to solve.

Answer :

Explanation:

27 + 10 = 37

We notice from the above figure that 27 is added to 10 means from 27 mustard yellow coloring starts for 10 numbers and stops at 36 . where 37 is the sum and it is highlighted with yellow color.

62 + 30 = 92

We notice from the above figure that 62 is added to 30 means from 62 mustard yellow coloring starts for 30 numbers and stops at 91 . where 92 is the sum and it is highlighted with yellow color.

**Show and Grow**

Question 1.

70 + 30 = ___

Answer :

Explanation :

The open number line start at 70 and 30 is same as 3 tens So, count on 3 tens .Then the linking jumps move to right from 70 to 100. It ends at 100 showing the sum .

So , 70 + 30 = 100 .

Question 2.

38 + 40 = ___

Answer :

38 + 40 = 78

Explanation :

The open number line start at 38 and 40 is same as 4 tens So, count on 4 tens .Then the linking jumps move to right from 38 to 78. It ends at 78 showing the sum .

So , 38 + 40 = 78

Question 3.

22 + 60 = ___

Answer :

22 + 60 = 82

Explanation :

The open number line start at 22 and 60 is same as 6 tens So, count on 6 tens .Then the linking jumps move to right from 22 to 82. It ends at 82 showing the sum .

So , 38 + 60 = 82

**Apply and Grow: Practice
**

Question 4.

60 + 30 = ___

Answer :

60 + 30 = 90

Explanation :

The open number line start at 60 and 30 is same as 3 tens So, count on 3 tens .Then the linking jumps move to right from 60 to 90. It ends at 90 showing the sum .

So , 60 + 30 = 90

Question 5.

51 + 20 = ___

Answer :

51 + 20 = 71

Explanation :

The open number line start at 51 and 20 is same as 2 tens So, count on 2 tens .Then the linking jumps move to right from 51 to 20. It ends at 20 showing the sum .

So , 51 + 20 = 71

Question 6.

49 + 50 = ___

Answer :

49 + 50 = 99

Explanation :

The open number line start at 49 and 50 is same as 5 tens So, count on 5 tens .Then the linking jumps move to right from 49 to 50. It ends at 99 showing the sum .

So , 49 + 50 = 99

Question 7.

**YOU BE THE TEACHER**

Your friend used an open number line to solve 40 + 20. Is your friend correct? Explain.

Answer :

Yes, he is correct.

40 + 20 = 60

Explanation :

The open number line start at 40 and 20 is same as 2 tens So, count on 2 tens .Then the linking jumps move to right from 40 to 60. It ends at 60 showing the sum .

So , 40 + 20 = 60

**Think and Grow: Modeling Real Life**

You have 66 berries and pick 30 more. Your friend picks 90 berries. Who has more berries?

Addition equation:

Model:

Answer :

Number of berries with me = 66

Number of berries picked by me = 30

Total Number of berries with me = 66 + 30 = 96

Number of berries with my friend = 90

I have more berries than my friend .

96 > 90 .

**Show and Grow**

Question 8.

You have 34 feathers and collect 50 more. Your friend has 85 feathers. Who has more feathers?

Answer :

Number of Feathers with me = 34

Number of features collected by me = 50

Total Number of features with me = 34 + 50 = 84

Number of features with my friend = 85

84 < 85

My friend is having more features than me

Question 9.

**DIG DEEPER!**

You have 49 stickers. Your friend gives you some more. Now you have 79. How many stickers did your friend give you?

Answer :

Number of stickers with me = 49

Total number of stickers with me now = 79

Number of stickers given by friend to me = 79 – 49 = 30

Therefore, Number of stickers given by friend to me = 30

### Add Tens Using a Number Line Homework & Practice 3.1

Question 1.

40 + 40 = ___

Answer :

40 + 40 = 80

Explanation :

The open number line start at 40 and 40 is same as 4 tens So, count on 4 tens .Then the linking jumps move to right from 40 to 80. It ends at 80 showing the sum .

So , 40 + 40 = 80

Question 2.

65 + 20 = ___

Answer:

65 + 20 = 85

Explanation :

The open number line start at 65 and 20 is same as 2 tens So, count on 2 tens .Then the linking jumps move to right from 65 to 20. It ends at 20 showing the sum .

So , 65 + 20 = 85

Question 3.

14 + 60 = ___

Answer :

14 + 60 =74

Explanation :

The open number line start at 14 and 60 is same as 6 tens So, count on 6 tens .Then the linking jumps move to right from 14 to 74. It ends at 74 showing the sum .

So , 14 + 60 = 74

Question 4.

**Number Sense**

Write an equation that matches the number line.

Answer :

Explanation :

The open number line start at 43 and 30 is same as 3 tens So, count on 3 tens .Then the linking jumps move to right from 43 to 30. It ends at 73 showing the sum .

So , 43 + 30 = 73

Question 5.

**Modeling Real Life**

Newton has 31 stamps and buys 20 more. Descartes has 50 stamps. Who has more stamps?

Answer :

Number of stamps with Newton = 31

Number of stamps bought by newton = 20

Total Number of stamps with newton = 31 + 20 = 51

Number of stamps with Descartes = 50

51 > 50

Newton have more stamps than Descartes .

Question 6.

**DIG DEEPER!**

You have 64 rocks. Your friend gives you some more. Now you have 94 rocks. How many rocks did your friend give you?

Answer :

Number of rocks with me = 64

Number of rocks given by friend = x

Total Number of rocks with me now = 94

Number of rocks given by friend = 94 – 64 = 30

Therefore, Number of rocks given by friend = 30

**Review & Refresh**

Question 7.

Answer :

15 is odd number

Explanation :

A number which is divisible by 2 and generates a remainder of 0 is called an even number.

Odd numbers are whole numbers that cannot be divided exactly into pairs. Odd numbers, when divided by 2, leave a remainder of 1. 1, 3, 5, 7, 9, 11, 13, 15 … are sequential odd numbers. Odd numbers have the digits 1, 3, 5, 7 or 9 in their ones place.

Question 8.

Answer :

8 is a even number as it is exactly divisible by 2

Explanation :

A number which is divisible by 2 and generates a remainder of 0 is called an even number.

Odd numbers are whole numbers that cannot be divided exactly into pairs. Odd numbers, when divided by 2, leave a remainder of 1. 1, 3, 5, 7, 9, 11, 13, 15 … are sequential odd numbers. Odd numbers have the digits 1, 3, 5, 7 or 9 in their ones place.

Question 9.

Answer :

12 is even number as it is exactly divisible by 2

Explanation :

A number which is divisible by 2 and generates a remainder of 0 is called an even number.

Odd numbers are whole numbers that cannot be divided exactly into pairs. Odd numbers, when divided by 2, leave a remainder of 1. 1, 3, 5, 7, 9, 11, 13, 15 … are sequential odd numbers. Odd numbers have the digits 1, 3, 5, 7 or 9 in their ones place.

### Lesson 3.2 Add Tens and Ones Using a Number Line

Color and show how you can use the hundred chart to solve.

Answer :

**Show and Grow**

Question 1.

69 + 12 = ___

Answer :

69 + 12 = 81

Explanation :

The open number line start at 69 and 12 is same as 1 tens and 2 ones So, count on 1 tens and 2 ones.Then the linking jumps move to right from 69 to 81. It ends at 81 showing the sum .

So , 69 + 12 = 81

Question 2.

55 + 34 = ___

Answer :

55 + 34 = 89

Explanation :

The open number line start at 55 and 34 is same as 3 tens and 4 ones So, count on 3 tens and 4 ones.Then the linking jumps move to right from 55 to 89. It ends at 89 showing the sum .

So , 55 + 34 = 89

**Apply and Grow: Practice**

Question 3.

15 + 32 = __

Answer:

15 + 32 = 47

Explanation :

The open number line start at 15 and 32 is same as 3 tens and 2 ones So, count on 3 tens and 2 ones.Then the linking jumps move to right from 15 to 32. It ends at 47 showing the sum .

So , 15 + 32 = 47

Question 4.

52 + 26 = ___

Answer :

52 + 26 = 78

Explanation :

The open number line start at 5 and 26 is same as 2 tens and 6 ones So, count on 2 tens and 6 ones. Then the linking jumps move to right from 52 to 26. It ends at 78 showing the sum .

So , 52 + 26 = 78

Question 5.

38 + 41 = ___

Answer :

38 + 41 = 79

Explanation :

The open number line start at 38 and 41 is same as 4 tens and 1 ones So, count on 4 tens and 1 ones.Then the linking jumps move to right from 38 to 41. It ends at 79 showing the sum .

So , 38 + 41 =79

Question 6.

65 + 33 = ___

Answer :

65 + 33 = 98

Explanation :

The open number line start at 65 and 33 is same as 3 tens and 3 ones So, count on 3 tens and 3 ones.Then the linking jumps move to right from 65 to 33. It ends at 98 showing the sum .

So , 65 + 33 = 98

Question 7.

**Reasoning**

Complete the number line and the equation.

Answer :

Explanation:

The open number line start at 46 . we have 2 tens and ___ ones. we have find the number of ones in the above figure. after adding two tens to the 46 we get 66 . if we add 4 to 66 only then the sum becomes 70. so the number ones are 4 .

Then the linking jumps move to right from 46 to 70. It ends at 70 showing the sum .

So , 46 + 24 = 70

Question 8.

There are 31 tadpoles. Then 19 more join them. How many tadpoles are there now?

Answer :

Number of tadpoles = 31

Number of tadpoles joined = 19

Total Number of tadpoles now = 31 + 19 = 50

Therefore, Total Number of tadpoles now = 50 .

**Think and Grow: Modeling Real Life**

Your class plants 21 trees. Your friend’s class plants 39. How many more trees does your friend’s class plant than your class?

Answer :

Number of plants planted by my class = 21

Number of plants planted my friend’s class = 39

Number of more trees does my friend’s class plant than my class = 39 – 21 = 18

**Show and Grow**

Question 9.

Your friend pops 76 bubbles on a piece of bubble wrap. You pop 88. How many more bubbles do you pop than your friend?

Answer :

Number of bubbles popped by my friend = 76

Number of bubbles popped by me = 88

Number of more bubbles popped by me than my friend = 88 – 76 = 12

Therefore, Number of more bubbles popped by me than my friend = 12

Question 10.

**DIG DEEPER!**

You have 45 bouncy balls. You ﬁnd some more. Now you have 91. How many bouncy balls did you ﬁnd?

Answer :

Number of bouncy balls with me = 45

Total Number of bouncy balls with me now = 91

Number of bouncy balls found by me = 91 – 45 = 46

Therefore Number of bouncy balls found by me = 46

### Add Tens and Ones Using a Number Line Homework & Practice 3.2

Question 1.

64 + 31 = ___

Answer :

64 + 31 = 95

Explanation :

The open number line start at 64 and 31 is same as 3 tens and 1 ones So, count on 3 tens and 1 ones .Then the linking jumps move to right from 64 to 95. It ends at 95 showing the sum .

So , 64 + 31 = 95

Question 2.

29 + 56 = ___

Answer :

29 + 56 = 85

Explanation :

The open number line start at 29 and 56 is same as 5 tens and 6 ones So, count on 5 tens and 6 Ones.Then the linking jumps move to right from 29 to 85. It ends at 85 showing the sum .

So , 29 + 56 = 85

Question 3.

18 + 62 = ___

Answer :

18 + 62 = 80

Explanation :

The open number line start at 18 and 62 is same as 6 tens and 8 ones So, count on 6 tens and 8 ones.Then the linking jumps move to right from 18 to 80. It ends at 80 showing the sum .

So , 18 + 62 = 80

Question 4.

72 + 11 = ___

Answer :

72 + 11 = 83

Explanation :

The open number line start at 72 and 11 is same as 1 tens and 1ones So, count on 1 tens and 1 ones.Then the linking jumps move to right from 72 to 83. It ends at 83 showing the sum .

So , 72 + 11 = 83

Question 5.

53 + 27 = ___

Answer :

53 + 27 = 80

Explanation :

The open number line start at 53 and 27 is same as 2 tens and 7 Ones So, count on 2 tens and 7 Ones. Then the linking jumps move to right from 53 to 80. It ends at 80 showing the sum .

So , 53 + 27 = 80

Question 6.

46 + 32 = ___

Answer :

46 + 32 = 78

Explanation :

The open number line start at 46 and 32 is same as 3 tens and 2 Ones So, count on 3 tens and 2 Ones. Then the linking jumps move to right from 46 to 78. It ends at 78 showing the sum .

So , 46 + 32 = 78

Question 7.

**Structure**

Show 27 + 43 two ways.

Answer :

27 + 43 = 70

43 + 27 = 70

Explanation :

The open number line start at 27 and 43 is same as 4 tens and 3 Ones So, count on 4 tens and 3 Ones .Then the linking jumps move to right from 27 to 70. It ends at 70 showing the sum .

So , 27 + 43 = 70

The open number line start at 43 and 27 is same as 2 tens and 7 Ones So, count on 2 tens and 7 Ones .Then the linking jumps move to right from 43 to 70. It ends at 70 showing the sum .

So , 43+ 27 = 70

Question 8.

**Modeling Real Life**

You bake 36 mufﬁns on Friday. You bake 24 on Saturday. How many more mufﬁns do you bake on Friday?

Answer :

Number of muffins baked on Friday = 36

Number of muffins baked on Saturday = 24

Number of muffins baked more on Friday than Saturday = 36 – 24 = 12

Therefore, 12 more mufﬁns are baked on Friday

Question 9.

**DIG DEEPER!**

Newton has 61 bugs. Then he ﬁnds some more. Now he has 78. How many bugs did Newton ﬁnd?

Answer :

Number of bugs with Newton = 61

Total Number of bugs with newton now = 78

Number of bugs found by Newton = 78 -61 = 17

**Review & Refresh**

Question 10.

Answer :

Explanation:

From the above picture we notice, 3 stack of ten cubes and 5 cubes so the Numbers have two digits. … The left digit is the tens’ place. It tells you that there are 3 tens. The last or right digit is the ones’ place which is 5. So,

Number is 35

Question 11.

Answer :

Explanation:

From the above picture we notice, 6 stack of ten cubes and 1 cube .the Numbers have two digits. … The left digit is the tens’ place. It tells you that there are 6 tens. The last or right digit is the ones’ place which is 1. So,

Number is 61

### Lesson 3.3 Use Place Value to Add

**Explore and Grow**

How can you use a model to solve?

Answer :

37 + 15 = 52

Explanation :

We use place value and break the addends into tens and ones. Then add the 10 tens values and ones values . Write the number formed . So, the number is 52

**Show and Grow**

Use place value to break apart the addends. Then find the sum.

Question 1.

Answer :

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 52

Question 2.

Answer :

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 87

Question 3.

Answer :

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 64

Question 4.

Answer :

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 92

**Apply and Grow: Practice**

Use place value to break apart the addends. Then find the sum.

Question 5.

Answer :

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 88

Question 6.

Answer :

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 99

Question 7.

Answer :

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 89

Question 8.

Answer :

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 46

Question 9.

Answer :

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 80

Question 10.

Answer :

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 63

Question 11.

**Number Sense**

Solve. Think: Does the same number make both equations true?

Answer :

No, it requires different numbers

16 + __________ = 27

16 + 11 = 27

____ + 27 = 48

21 + 27 = 48

**Think and Grow: Modeling Real Life**

You use 72 blocks to make a building. Your friend uses 14 more than you. How many blocks does your friend use?

Addition equation:

Answer :

Number of blocks used by me = 72

Number of blocks used by my friend = 72 + 14 = 86

Addition Equation :

72 + 14 = 86

**Show and Grow**

Question 12.

Your friend has 57 beads. You have 21 more than your friend. How many beads do you have?

Answer :

Number of beads with my friend = 57

Number of beads with me = 57 + 21

Addition equation :

57 + 21 = 78

Explanation :

Question 13.

You have 68 grapes. 38 are red. The rest are green. How many grapes are green?

Answer :

Number of grapes with me = 68

Number of red grapes = 38

Number of green grapes = 68 – 38 = 40

Therefore, Number of green grapes = 40 .

### Use Place Value to Add Homework & practice 3.3

Use place value to break apart the addends. Then find the sum.

Question 1.

Answer :

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 92

Question 2.

Answer :

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 88

Question 3.

Answer :

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 100

Question 4.

Answer :

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 91

Question 5.

**DIG DEEPER!**

You buy two packs of pens. You buy 49 pens in all. Which color pens do you buy?

Answer :

Total pens = 49

Number of blue pens = 25

Number of black pens = 12

Total blue and black pens = 25 + 12 = 37

Total blue black are not equal to 49 so these are not bought .

Number of red pens = 24

Total number of blue and black pens = 25 + 24 = 49

Therefore the color pens which are bought are black and blue as there total numbers pens are equal to 49 .

Question 6.

**Modeling Real Life**

Newton picks 41 ﬂowers. Descartes picks 28 more than Newton. How many ﬂowers does Descartes pick?

Answer :

Number of flowers picked by Newton = 41

Number of flowers picked by Descartes = 28 more than Newton = 28 + 41 = 69

Question 7.

**Modeling Real Life**

You have 57 marbles. 36 are yellow. The rest are blue. How many blue marbles do you have?

Answer :

Number of marbles with me = 57

Number of yellow marbles = 36

Number of blue marbles = total marbles – yellow marbles = 57 – 36 = 21

Therefore, Number of blue marbles = 21 .

**Review & Refresh**

Question 8.

Answer :

Explanation:

The number before rows tell us how many groups we have.

The number after rows tell us how many are in each group.

The number at the end, after the equal signs is the total number of items .

we add number of items in each row as many times of number of rows .

Question 9.

Answer :

Explanation:

The number before rows tell us how many groups we have.

The number after rows tell us how many are in each group.

The number at the end, after the equal signs is the total number of items .

we add number of items in each row as many times of number of rows .

### Lesson 3.4 Decompose to Add Tens and Ones

**Explore and Grow**

Use a model to solve.

Which addend did you break apart to add ? Explain.

________________________________

________________________________

________________________________

Answer :

50 + 18 = 68

Explanation :

The addend which we break apart to add is 18 . Break 18 into tens and ones that is 10 + 8. Add the tens to the first addend that is 50 + 10 = 60. Then add the ones that is 60 + 8 = 68.

So, the sum is 68 .

**Show and Grow**

Use place value to break apart an addend. Then find the sum.

Question 1.

Answer :

Explanation :

The addend which we break apart to add is 12 . Break 12 into tens and ones that is 10 + 2. Add the tens to the first addend that is 61 + 10 = 71. Then add the ones that is 71 + 2 = 73.

So, the sum is 73 .

Question 2.

Answer :

Explanation :

The addend which we break apart to add is 24 . Break 24 into tens and ones that is 20 + 4. Add the tens to the first addend that is 74 + 20 = 94. Then add the ones that is 94 + 4 = 98.

So, the sum is 98.

Question 3.

Answer :

Explanation :

The addend which we break apart to add is 44 . Break 44 into tens and ones that is 40 + 4. Add the tens to the first addend that is 23 + 40 = 63. Then add the ones that is 63 + 4 = 67.

So, the sum is 67 .

Question 4.

Answer :

Explanation :

The addend which we break apart to add is 53 . Break 53 into tens and ones that is 50 + 3. Add the tens to the first addend that is 31 + 50 = 81. Then add the ones that is 81 + 3 = 84.

So, the sum is 84 .

**Apply and Grow: Practice**

Use place value to break apart an addend. Then find the sum.

Question 5.

Answer :

Explanation :

The addend which we break apart to add is 11 . Break 11 into tens and ones that is 10 + 1. Add the tens to the first addend that is 71 + 10 = 81. Then add the ones that is 81 + 1 = 82.

So, the sum is 82 .

Question 6.

Answer :

Explanation :

The addend which we break apart to add is 23 . Break 23 into tens and ones that is 20 + 3. Add the tens to the first addend that is 65 + 20 = 85. Then add the ones that is 85 + 3 = 88.

So, the sum is 88

.

Question 7.

Answer :

Explanation :

The addend which we break apart to add is 47 . Break 47 into tens and ones that is 40 + 7. Add the tens to the first addend that is 32 + 40 = 72. Then add the ones that is 72 + 7 = 79.

So, the sum is 79 .

Question 8.

Answer :

Explanation :

The addend which we break apart to add is 43 . Break 43 into tens and ones that is 40 + 3. Add the tens to the first addend that is 25 + 40 = 65. Then add the ones that is 65 + 3 = 68.

So, the sum is 68 .

Question 9.

54 + 36 = ___

Answer :

Explanation :

The addend which we break apart to add is 36 . Break 36 into tens and ones that is 30 + 6. Add the tens to the first addend that is 54 + 30 = 84. Then add the ones that is 84 + 6 = 90.

So, the sum is 90 .

Question 10.

21 + 61 = ___

Answer :

Explanation :

The addend which we break apart to add is 61 . Break 61 into tens and ones that is 60 + 1. Add the tens to the first addend that is 21 + 60 = 81. Then add the ones that is 81 + 1 = 82.

So, the sum is 82 .

Question 11.

**Precision**

Which expressions have a sum of 72.

Answer :

Two Equations 41 + 31 and 11 + 61 have sum of 72 .

Explanation :

52 + 22 = 74

51 + 11 = 62

41 + 31 = 72

47 + 30 = 77

11 + 61 = 72

**Think and Grow: Modeling Real Life**

You have 32 coins in a piggy bank. You put in 45 more. How many coins are in the bank now?

Addition equation:

Answer :

Number of Coins = 32

Number of coins added in piggy bank = You put in 45 more = 32 + 45 = 77

Therefore, Number of coins in bank = 77

**Show and Grow**

Question 12.

There are 81 fans at a game. 18 more arrive. How many fans are at the game now?

Answer :

Number of fans = 81

Number of fans arrived = 18 more

Number of fans at the game = 81 + 18 = 99 fans .

Question 13.

You have 54 songs on a music player. Your friend has 31 more than you. How many songs does your friend have ?

Answer :

Number of songs in my music player = 54

Number of songs my friend have = 31 more than me = 31 + 54 = 85

### Decompose to Add Tens and Ones Homework & Practice 3.4

Use place value to break appart an addend. Then find the sum.

Question 1.

Answer :

Explanation :

The addend which we break apart to add is 34 . Break 34 into tens and ones that is 30 + 4. Add the tens to the first addend that is 53 + 30 = 83. Then add the ones that is 83 + 4 = 87.

So, the sum is 87 .

Question 2.

Answer :

Explanation :

The addend which we break apart to add is 13 . Break 13 into tens and ones that is 10 + 3. Add the tens to the first addend that is 46 + 10 = 56. Then add the ones that is 56 + 3 = 59.

So, the sum is 59 .

Question 3.

Answer :

Explanation :

The addend which we break apart to add is 73 . Break 73 into tens and ones that is 70 + 3. Add the tens to the first addend that is 14 + 70 = 84. Then add the ones that is 84 + 3 = 87.

So, the sum is 87 .

Question 4.

Answer :

Explanation :

The addend which we break apart to add is 67 . Break 67 into tens and ones that is 60 + 7. Add the tens to the first addend that is 31 + 60 = 91. Then add the ones that is 91 + 7 = 98.

So, the sum is 98 .

Question 5.

28 + 61 = ___

Answer :

Explanation :

The addend which we break apart to add is 28 . Break 28 into tens and ones that is 60 + 1. Add the tens to the first addend that is 28 + 60 = 88. Then add the ones that is 88 + 1 = 89.

So, the sum is 89 .

Question 6.

51 + 41 = ___

Answer :

Explanation :

The addend which we break apart to add is 41 . Break 41 into tens and ones that is 40 + 1. Add the tens to the first addend that is 51 + 40 = 91. Then add the ones that is 91 + 1 = 92.

So, the sum is 92 .

Question 7.

**DIG DEEPER!**

Use the numbers to complete the equation.

Answer :

Question 8.

**Modeling Real Life**

You see 38 ladybugs. Then you see 21 more. How many ladybugs do you see?

Answer :

Number of lady bugs seen = 38

Number of Lady bugs seen later = 21 more = 38 + 21 = 59

Therefore, Total Number of lady bugs seen = 59

Question 9.

**Modeling Real Life**

You read for 18 minutes and play outside for 35 minutes. How many minutes do you read and play in all?

Answer :

Minutes used for reading = 18

Minutes used to played = 35

Number of Minutes used to read and play = 18 + 35 = 53

**Review & Refresh**

Question 10.

Draw a line through the shorter object.

Answer :

### Lesson 3.5 Use Compensation to Add

**Explore and Grow**

Match the numbers that make a ten.

How can making a ten help you add greater numbers?

_________________________________

_________________________________

_________________________________

Answer :

Explanation :

Making a ten help you us in adding numbers easily . It helps to divide the addend into tens part and ones part. tens parts can be easily added to any numbers then later the ones part is added .

**Show and Grow**

Use compensation to add.

Question 1.

Answer :

Explanation :

Takes ones from one addend to make other addend number a decade number . Here 1 is taken from addend 5 and added to 59 addend to make 59 a decade number that is 59 + 1 = 60

Then add the changed addends we get, 4 + 60 = 64 .

Question 2.

Answer :

Explanation :

Takes ones from one addend to make other addend number a decade number . Here 4 is taken from addend 37 and added to 16 addend to make 16 a decade number that is 16 + 4 = 20

Then add the changed addends we get, 33 + 20 = 53 .

**Apply and Grow: Practice**

Use compensation to add.

Question 3.

52 + 19 = ?

Answer :

Explanation :

Takes ones from one addend to make other addend number a decade number . Here 1 is taken from addend 52 and added to 19 addend to make 19 a decade number that is 19 + 1 = 20

Then add the changed addends we get, 51 + 20 = 71 .

Question 4.

43 + 8 = ?

Answer :

Explanation :

Takes ones from one addend to make other addend number a decade number . Here 2 is taken from addend 43 and added to 8 addend to make 8 a decade number that is 8 + 2 = 10

Then add the changed addends we get, 41+ 10 = 51 .

Question 5.

26 + 35 = ?

Answer :

Explanation :

Takes ones from one addend to make other addend number a decade number . Here 5 is taken from addend 26 and added to 35 addend to make 35 a decade number that is 35 + 5 = 40

Then add the changed addends we get, 21 + 40 = 61 .

Question 6.

68 + 15 = ?

Answer :

Explanation :

Takes ones from one addend to make other addend number a decade number . Here 5 is taken from addend 68 and added to 15 addend to make 15 a decade number that is 15 + 5 = 20

Then add the changed addends we get, 63+ 20 = 83 .

Question 7.

**Structure**

Show two different ways to use compensation to find 25 + 17.

Answer :

Explanation :

Takes ones from one addend to make other addend number a decade number . Here 3 is taken from addend 25 and added to 17 addend to make 17 a decade number that is 17 + 3= 20

Then add the changed addends we get, 22+ 20 = 42 .

Takes ones from one addend to make other addend number a decade number . Here 5 is taken from addend 17 and added to 25 addend to make 25 a decade number that is 25 + 5= 30

Then add the changed addends we get, 30+ 12= 42 .

**Think and Grow: Modeling Real Life**

You need 100 tickets for a prize. You have 79 and win 17 more. Do you have enough tickets for a prize?

Addition equation:

Answer :

Number of Tickets for a prize = 100

Number of tickets with me = 79

Number of tickets won = 17

Total Number of tickets with me = 79 + 17 = 96

100 > 96 .

No, I don’t have enough tickets for a prize .

**Show and Grow**

Question 8.

You need to set up 80 chairs. You set up 32. Your friend sets up 49. Do you and your friend set up enough chairs?

Answer :

Numbers chairs required to setup = 80

Number of chairs set up by me = 32

Number of chairs set up by my friend = 49

Total chairs set up by me and my friend = 32 + 49 = 81

80 < 81

Yes, me and my friend set up enough chairs .

Question 9.

**DIG DEEPER!**

You need 50 containers of slime for a party. You have 28. You buy 17 more. How many more containers do you need?

Answer :

Number of containers required for slime a party = 50

Number of containers with me = 28

Number of containers bought = 17

Total Number of containers with me = 28 + 17 =45

Number of containers required more = 50 – 45 = 5

### Use Compensation to Add Homework & Practice 3.5

Use compensation to add.

Question 1.

Answer :

Explanation :

Takes ones from one addend to make other addend number a decade number . Here 1 is taken from addend 31 and added to 46 addend to make 31 a decade number that is 31 – 1 = 30

Then add the changed addends we get, 47+ 30 = 77 .

Question 2.

Answer :

Explanation :

Takes ones from one addend to make other addend number a decade number . Here 5 is taken from addend 27 and added to 15 addend to make 15 a decade number that is 15 + 5 = 20

Then add the changed addends we get, 22+ 20 = 42 .

Question 3.

Answer :

Explanation :

Takes ones from one addend to make other addend number a decade number . Here 4 is taken from addend 34 and added to 66 addend to make 66 a decade number that is 34 – 4 = 30

Then add the changed addends we get, 70+ 30 = 100 .

Question 4.

Answer :

Explanation :

Takes ones from one addend to make other addend number a decade number . Here 1 is taken from addend 56 and added to 29 addend to make 29 a decade number that is 29 + 1 = 30

Then add the changed addends we get, 55+ 30 = 85 .

Use compensation to add.

Question 5.

Answer :

Explanation :

Takes ones from one addend to make other addend number a decade number . Here 4 is taken from addend 75 and added to 6 addend to make 6 a decade number that is 6 + 4 = 10

Then add the changed addends we get, 71+ 10 = 81 .

Question 6.

Answer :

Explanation :

Takes ones from one addend to make other addend number a decade number . Here 2 is taken from addend 44 and added to 38 addend to make 38 a decade number that is 38 + 2 = 40

Then add the changed addends we get, 42+ 40 = 84 .

Question 7.

**Writing**

Explain why you make one addend a decade number when using compensation to add.

________________________________

________________________________

________________________________

Answer :

Addends are numbers used in addition problems, they refers to the numbers that are added together. … When solving addition problems, it is advisable to make one of the addends a tens number because, it makes the addition operation easier to manipulate.

Compensation is a mental math strategy for multi-digit addition that involves adjusting one of the addends to make the equation easier to solve. Some students may prefer this strategy as an alternative to left-to-right addition or the breaking up the second number strategy.

Question 8.

**Modeling Real Life**

You want to read 50 pages. You read 18 on Monday and 27 on Tuesday. Do you reach your goal?

Answer :

Number of pages i want to read = 50

Number of pages read on Monday = 18

Number of pages read on Tuesday = 27

Number of pages read by me on Monday and Tuesday = 18 + 27 = 45

50 > 45 .

No, I didn’t reach the goal. More 5 pages required to read .

**Review & Refresh**

Draw one line to show the parts

Question 9.

2 squares

Answer :

Explanation :

The above rectangle is divided into 2 squares by drawing a line in the middle of the rectangle. it is drawn on half of the length of the rectangle .

Question 10.

2 triangles

Answer :

Explanation :

Draw any line from any of the vertexes of the triangle . It divided the given triangle into two equal triangles as shown in the above diagram .

### Lesson 3.6 Practice Addition Strategies

**Explore and Grow**

Use any strategy to ﬁnd the sum.

Compare your strategy to your partner’s strategy. How are your strategies alike? How are they different?

________________________________

________________________________

________________________________

Answer :

Explanation :

In the first method We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 76

In the Second Method The addend which we break apart to add is 41 . Break 41 into tens and ones that is 40 + 1. Add the tens to the first addend that is 35 + 40 = 75. Then add the ones that is 75 + 1 = 76.

So, the sum is 76 .

**Show and Grow**

Question 1.

50 + 35 = ___

Answer :

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 85

Question 2.

64 + 32 = ___

Answer :

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 96

Question 3.

19 + 26 = ___

Answer :

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 45

Question 4.

78 + 13 = ___

Answer :

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 91

**Apply and Grow: Practice**

Question 5.

32 + 41 = ___

Answer :

Explanation :

The addend which we break apart to add is 41 . Break 41 into tens and ones that is 40 + 1. Add the tens to the first addend that is 32 + 40 = 72. Then add the ones that is 72 + 1 = 73.

So, the sum is 73 .

Question 6.

56 + 18 = ___

Answer :

Explanation :

The addend which we break apart to add is 18 . Break 18 into tens and ones that is 10 + 8. Add the tens to the first addend that is 56 + 10 = 66. Then add the ones that is 66 + 8 = 74.

So, the sum is 74 .

Question 7.

47 + 36 = ___

Answer :

Explanation :

The addend which we break apart to add is 36 . Break 36 into tens and ones that is 30 + 6. Add the tens to the first addend that is 47 + 30 =77 . Then add the ones that is 77 + 6 = 83.

So, the sum is 83 .

Question 8.

91 + 9 = ___

Answer :

Explanation :

The addend which we break apart to add is 9 . Break 9 into tens and ones that is 10 – 1. Add the tens to the first addend that is 91 + 10 = 101. Then add the ones that is 101 – 1 = 100.

So, the sum is 100 .

Question 9.

___ = 67 + 22

Answer :

Explanation :

The addend which we break apart to add is 22 . Break 22 into tens and ones that is 20 + 2. Add the tens to the first addend that is 67 + 20 =87 . Then add the ones that is 87 + 2 = 89.

So, the sum is 89 .

Question 10.

__ = 51 + 39

Answer :

Explanation :

The addend which we break apart to add is 39 . Break 39 into tens and ones that is 30 + 9. Add the tens to the first addend that is 51 + 30 = 81 . Then add the ones that is 51 + 39 = 90.

So, the sum is 90 .

Question 11.

**YOU BE THE TEACHER**

Your friend breaks apart an addend to solve 24 + 56. Is your friend correct? Explain.

Answer :

Yes , he is correct.

Explanation :

The addend which we break apart to add is 56 . Break 56 into tens and ones that is 50 + 6. Add the tens to the first addend that is 24 + 50 = 74 . Then add the ones that is 74 + 6 = 80.

So, the sum is 80 .

**Think and Grow: Modeling Real Life**

You collect 23 cans of a food drive. Your friend collects 35 more than you. How many cans does your friend collect?

Answer :

Number of cans collected by me = 23

Number of cans collected by my friend = 35 more than me

Number of cans collected by my friend = 35+ 23 = 58

**Show and Grow**

Question 12.

You jump rope 67 times today. Tomorrow you want to jump rope 15 more times than you did today. How many times should you jump rope tomorrow?

Answer :

Number of rope jumps today by me = 67

Number of rope jumps by me for tomorrow = 15 more times than you did today

Number of rope jumps by me for tomorrow = 15 + 67 = 82

Question 13.

Your friend uses 19 fewer nails than you to build a birdhouse. Your friend uses 13 nails. How many nails do you use?

Answer :

Number of nails used by my friend = 13

Number of nails used by me = x

Your friend uses 19 fewer nails than me

x – 19 = 13

x = 13 + 19

x = 32

Therefore , Number of nails used by me = 32

Question 14.

The book club has 27 fewer students than the art club. The book club has 24 students. How many students are in the art club?

Answer :

Number of students in book club = Numbers of students in art club – 27

Number of students in book club = 24

Numbers of students in art club = 24 + 27 (From given condition ) = 51

### Practice Addition Strategies Homework & Practice 3.6

Question 1.

20 + 40 = __

Answer :

20 + 40 = 60

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 60

Question 2.

60 + 26 = ___

Answer :

60 + 26 = 86

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 86

Question 3.

19 + 61 = ___

Answer :

19 + 61 = 80

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 80

Question 4.

43 + 28 = ___

Answer :

43 + 28 = 71

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 71

Question 5.

__ = 45 + 46

Answer :

45 + 45 = 91

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 91

Question 6.

__ = 33 + 59

Answer :

33 + 59 = 92

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 92

Question 7.

**YOU BE THE TEACHER**

Your friend uses compensation to solve 28 + 33. Is your friend correct? Explain.

Answer :

No , he is wrong .

Explanation :

After adding 2 to 28 then we should subtract 2 from 33 .then we get 28 + 2 = 30 and 33 – 2 = 31 . now add the changed addends we get 30 + 31 = 61 .

So, the sum is 61 .

Question 8.

**Modeling Real Life**

You have 15 blue crayons and 26 red crayons. How many crayons do you have in all?

Answer :

Number of blue crayons = 15

Number of red crayons = 26

Total number of crayons = 15 + 26 = 41

Question 9.

**Modeling Real Life**

The home team scores 46 points. The visiting team scores 13 more than the home team. How many points does the visiting team score?

Answer :

Score of home team = 46

Score of visiting team = 13 more than the home team = 13 + 46 = 59

Therefore, visiting team score = 59 points .

**Review & Refresh**

Question 10.

Answer :

Number of Drums = 5

Number of Guitars = 5 + 4 = 9

5< 9

It means number of Guitars are greater than number of drums.

### Lesson 3.7 Problem Solving: Addition

Model the story.

Newton has 15 books. Descartes has 22 more. How many books does Descartes have?

Answer :

Number of books with Newton =15

Number of books with Descartes = 22 more = 22 + 15 = 37

How many books do Newton and Descartes have in all?

Answer :

Total Number of books with Newton and Descartes = 15 + 37 = 52

**Show and Grow**

Question 1.

You have 7 cherries. You pick 6 more. Your friend has 45 cherries. How many cherries do you and your friend have in all?

Answer :

Number of cherries with me = 7

Number pf cherries picked by me = 6

Total Number of cherries with me = 7 + 6 = 13

Number of cherries with my friend = 45

Total Number of cherries with me and my friend = 13 + 45 = 58

**Apply and Grow: Practice**

Question 2.

You have 15 blueberries. You pick 12 more. Your friend picks 32 blueberries. How many blue berries do you and your friend pick in all?

Answer :

Number of blueberries with me = 15

Number of blueberries picked by me = 12 more

Total Number of blueberries with me = 15 + 12 = 27

Number of blueberries with my friend = 32

Total Number of blueberries with me and my friend = 27 + 32 = 59

Question 3.

You have 26 green crayons. You ﬁnd 10 more. You have 16 red crayons. How many crayons do you have in all?

Answer :

Number of Green crayons with me = 26

Number of green crayons found = 10

Total Number of green crayons = 26 + 10 = 36

Number of red crayons = 16

Total Number of crayons = 36 + 16 = 52

Question 4.

You take 24 pictures on Friday. You take 20 more on Saturday. You and your friend take 50 pictures in all. How many pictures does your friend take?

Answer :

Number of pictures taken on Friday by me= 24

Number of pictures taken on Saturday by me = 20 + 24 = 44

Number of pictures taken by me and my friend = 50

Number of pictures taken by friend = 50 – 44 = 6

**Think and Grow: Modeling Real Life**

There are 31 children at a craft fair. There are 20 more adults than children at the craft fair. How many people are at the craft fair in all?

Circle what you know.

Underline what you need to ﬁnd.

Solve:

Answer :

Number of children at craft fair= 31

Number of adults at craft fair = 20 more than children’s = 20 + 31 = 51

Total Number of people at craft fair = 31 + 51 = 82.

**Show and Grow**

Question 5.

Your friend has 40 pens. You have 16 more than your friend. How many pens do you and your friend have in all?

Answer :

Number of pens with my friend = 40

Number of pens with me = 16 more than my friend. = 16 + 40 = 56 .

Total Number of pens with me and my friend = 40 + 56 = 96

Question 6.

You plant 28 seeds. Your friend plants 13 more than you. How many seeds do you and your friend plant in all?

Answer :

Number of seeds planted by me = 28

Number of seeds planted by my friend = 13 more than me = 13 + 28 = 41

Total Number of seeds planted by me and my friend = 28 + 41 = 69

### Problem Solving: Addition Homework & Practice 3.7

Question 1.

You see 14 zebras and 4 elephants at the zoo. Then you see 20 snakes. How many animals do you see in all?

Answer :

Number of zebras = 14

Number of elephants = 4

Number of snakes = 20

Total Number of animals = Number of zebras + Number of elephants + Number of snakes = 14 + 4 + 20 = 38

Question 2.

You win 14 tokens at one game and 15 at another. You and your friend have 40 tokens in all. How many tokens does your friend have?

Answer :

Number of tokens won in one game = 14

Number of tokens won in another game = 15

Total Number of tokens with me = 14 + 15 = 29

Number of tokens with me and my friend = 40

Number of tokens with my friend = total tokens – number of tokens with me = 40 – 29 = 11

Question 3.

Your class sells 40 rafﬂe tickets. Your friend’s class sells 15 more than your class. How many rafﬂe tickets do your class and your friend’s class sell in all?

Answer :

Number of raffle tickets sold by my class = 40

Number of tickets sold my friends class = 15 more than my class = 15 + 40 = 55

Total Number of tickets sold by my class and friends class = 40 + 55 = 95

Question 4.

**Modeling Real Life**

Your friend picks 33 apples. You pick 11 more than your friend. How many apples do you and your friend pick in all?

Answer :

Number of apples picked my friend = 33

Number of apples picked by me = 11 more than my friend = 11 + 33 = 44

Total Number of apples with me and my friend = 33 + 44 = 77 apples.

**Review & Refresh**

Get to 10 to subtract

Question 5.

Answer :

Question 6.

Answer :

### Addition to 100 Strategies Performance Task 3

Question 1.

You go to an amusement park. The wait times and ride times for the rides are shown below.

a. Find the total number of minutes it takes to wait and ride each ride.

Answer :

Total Time = Wait time + Ride Time

b. How many more minutes do you spend at the log ride than at the bumper cars?

Answer :

Number of minutes at log ride = 68 minutes.

Number of minutes at Bumper cars = 44 minutes .

Number of more minutes spend at the log ride than at the bumper cars = 68 – 44 = 24 minutes.

c. You want to ride 2 different rides in less than 90 minutes. Which rides can you ride?

Answer :

The two rides which i can ride less than 90 minutes are Ferris wheel and Bumper cars.

Explanation :

Number of minutes at Ferris wheel = 42

Number of minutes at Bumper cars = 44

Total Time = 42 + 44 = 86

86 > 90 minutes.

Question 2.

At 12:30, you spend 25 minutes eating lunch and 30 minutes playing games. How many more minutes are there until the show starts?

Answer :

Time spent in eating lunch = 25 minutes

Time spent in playing games = 30 minutes

Total Time = 25 + 30 = 55 minutes

From 12 : 30 total time spent is 55 minutes so the time is 1:25

The show starts at 1 : 30.

The time left to start the show is 5 minutes.

### Addition to 100 Strategies Activity

**Three in a Row: Addition**

To Play: Players take turns. On your turn, spin both spinners. Add the two numbers and cover the sum. Continue playing until a player gets three in a row.

### Addition to 100 Strategies Chapter Practice 3

**3.1 Add Tens Using a Number Line**

Question 1.

30 + 40 = __

Answer :

Explanation :

The open number line start at 30 and 40 is same as 4 tens So, count on 4 tens .Then the linking jumps move to right from 30 to 70. It ends at 70 showing the sum .

So , 30 + 40 = 70

Question 2.

26 + 50 = ___

Answer :

Explanation :

The open number line start at 26 and 50 is same as 5 tens So, count on 5 tens .Then the linking jumps move to right from 26 to 70. It ends at 76 showing the sum .

So , 26 + 50 = 76

**3.2 Add Tens and Ones Using a Number Line**

Question 3.

46 + 33 = ___

Answer :

Explanation :

The open number line start at 46 and 33 is same as 3 tens and 3 ones So, count on 3 tens and 3 ones.Then the linking jumps move to right from 46 to 79. It ends at 79 showing the sum .

So , 46 + 33 = 79 .

Question 4.

**Modeling Real Life**

You ﬁnd 57 bugs. Your friend ﬁnds 12 more than you. How many bugs does your friend ﬁnd?

Answer :

Number of bugs found by me = 57

Number of bugs found by my friend = 12 more than you = 57 + 12 = 69

Explanation :

The open number line start at 57 and 12 is same as 1 tens and 2 ones So, count on 1 tens and 2 ones.Then the linking jumps move to right from 57 to 69. It ends at 69 showing the sum .

So , 57 + 12 = 69

**3.3 Use Place Value o Add**

Use place value to break apart the addends. Then ﬁnd the sum.

Question 5.

Answer :

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 87

Question 6.

Answer :

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 86

Question 7.

Answer :

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 96

Question 8.

Answer :

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 81

**3.4 Decompose to Add Tens and Ones**

Use place value to break apart an addend. Then find the sum.

Question 9.

Answer :

Explanation :

The addend which we break apart to add is 42 . Break 42 into tens and ones that is 40 + 2. Add the tens to the first addend that is 37 + 40 = 77. Then add the ones that is 77 + 2 = 79.

So, the sum is 79 .

Question 10.

Answer :

Explanation :

The addend which we break apart to add is 26 . Break 26 into tens and ones that is 20 + 6. Add the tens to the first addend that is 51 + 20 = 71. Then add the ones that is 71 + 6 = 77.

So, the sum is 77 .

Question 11.

**Precision**

Which expressions have a sum of 95?

Answer :

Expressions : 43 + 52 , 31 + 64 and 73 + 22 have sum of 95

Explanation :

43 + 52 = 95

25 + 30 = 55

31 + 64 = 95

73 + 22 = 95

71 + 12 = 83

**3.5 Use Compensation to Add**

Use compensation to add.

Question 12.

Answer :

Explanation :

Takes ones from one addend to make other addend number a decade number . Here 5 is taken from addend 66 and added to 25 addend to make 25 a decade number that is 25 + 5 = 30

Then add the changed addends we get, 61 + 30 = 91 .

Question 13.

Answer :

Explanation :

Takes ones from one addend to make other addend number a decade number . Here 1 is taken from addend 53 and added to 39 addend to make 39 a decade number that is 39+ 1 = 40

Then add the changed addends we get, 52 + 40 = 92 .

Question 14.

**Modeling Real Life**

You and your friend want to ﬁnd 90 seashells. You ﬁnd 45. Your friend ﬁnds 51. Do you and your friend reach your goal?

Answer :

Total Numbers of seashells to be found = 90

Number of shells found by me = 45

Number of shells found by my friend = 51

Total Number of shells found by me and my friend = 45 + 51 = 96

90 < 96 .

Yes, we reached the goal .

**3.6 Practice Addition Strategies**

Question 15.

47 + 36 = __

Answer :

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 83

Question 16.

50 + 19 = ___

Answer :

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 69

Question 17.

32 + 55 = ___

Answer :

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 87

Question 18.

54 + 26 = ___

Answer :

Explanation :

We use place value and break the addends into tens and ones. Then add the tens values and ones values .Write the number formed . So, the number is 80

**3.7 Problem Solving: Addition**

Question 19.

Newton has 23 rocks. He ﬁnds 7 more. Descartes has 51 rocks. How many rocks do Newton and Descartes have in all?

Answers :

Number of rocks with Newton = 23

Number of rocks found by newton = 7

Total number of rocks with newton = 23 + 7 = 30

Number of rocks with Descartes = 51

Total Number of rocks with Newton and Descartes = 30 + 51 = 81

Question 20.

Your friend has 22 bracelets. You have 16 more. How many bracelets do you and your friend have in all?

Answer :

Number of bracelets with my friend = 22

Number of bracelets with me = 16

Total Number of bracelets with me and my friend = 22 + 16 = 38 Bracelets

Therefore, Total Number of bracelets with me and my friend = 38 Bracelets .