All the solutions provided in McGraw Hill Math Grade 4 Answer Key PDF Chapter 5 Lesson 4 Multiply by a Two-Digit Number will give you a clear idea of the concepts.
McGraw-Hill My Math Grade 4 Answer Key Chapter 5 Lesson 4 Multiply by a Two-Digit Number
Math in My World
Example 1
A coyote travels 27 miles each hour. How far can a coyote travel in 12 hours?
Find 27 × 12.
One Way Use partial products.
Draw an area model. Separate each factor into tens and ones. Multiply. 20 Then add the partial products.
200 + 40 + 70 + 14 = _____
Another Way Use paper and pencil.
27 × 12 = ____
So, a coyote can travel ____ miles in 12 hours.
Answer: So, a coyote can travel 324 miles in 12 hours.
Explanation: Given the data is,
A coyote travels 27 miles each hour.
Now, we will find out how far can a coyote travel in 12 hours.
We have two methods for finding the distance,
One method is using the area model:
Next add 200 + 70 + 40 + 14 = 324.
So, the product of 27 and 12 is 324. Hence, Coyote travels 324 miles in 12 hours.
Another method using the multiplication:
The product of 27 and 12 is,
Therefore, the product value is 324 values. Hence, a Coyote travels 324 miles in 12 hours.
Example 2
Heidi’s monthly bills are shown. How much does she spend on her cell phone service in 2 years?
Write an equation to help you solve the problem.
You know that 12 × 2 = 24. So, you need to find $38 × 24.
Estimate ___ × ____ = _____
So, the cost of cell phone service for 2 years is $ _____
Check
____ is close to the estimate of ____.
Answer: So, the cost of cell phone service for 2 years is $912.
$912 is close to the estimate of $800.
Explanation: Given that,
Heidi’s monthly cell phone bill is $38.
Now, we will find out how much money he spent for 2 years.
We know that 1 year = 12 months,
For 2 years, 2 x 12 = 24 months.
So, we find the value of $38 x 24.
First, estimate the value to the nearest tens.
The value 38 is rounded off to 40 and the value 24 is rounded off to 20.
Then the product of $40 x 20 = $800.
Now, we will find the product value of $38 and 24 is,
The product value is $912.
Therefore, for 2 years he spent $912 on his cell phone service. Hence, the estimated value of $800 is approximately tp $912.
Talk Math
Explain the steps needed to find the product of 56 and 23.
Answer: The steps need to multiply the 56 and 23 for the product value is,
Step 1: First, multiply with tens.
Step 2: Multiply with ones.
Step 3: Add the product values.
The below figure shows the procedure of steps.
Therefore, using the steps the product value is 1288.
Guided Practice
Multiply.
Question 1.
The area model shows that 600 + 120 + 100 + 20 = _____
Answer: The product value 0f 35 and 24 is 600 + 120+ 100 + 20 is 840.
Explanation: Given that, the values are 35 and 24.
Now, we will find the product value.
So, the values are 35 and 24,
Hence, the product value is 840.
Independent Practice
Multiply. Use the area model to check.
Question 2.
Answer: 285
Explanation: Given that, the values are 19 and 15.
Now, we will find the product value.
So, the values are 19 and 15.
Add 100 + 90 + 50 + 45 = 285
Therefore, the product value is 285.
Question 3.
Answer: 1596
Explanation: Given that, the values are 42 and 38.
Now, we will find the product value.
So, the values are 42 and 38 using the area model we can find the value,
Add the values are 1200 + 320 + 60 + 16 = 1596.
Therefore, the product value is 1596.
Question 4.
Answer: $2754
Explanation: Given that, the values are $54 and 51.
Now, we will find the product value using the area model.
So, the values are 54 and 51 ,
Add 2500 + 200 + 50 + 4 = 2754.
Hence the product of the given values is $2754.
Question 5.
Answer: $4662
Explanation: Given that, the values are $74 and 63.
Now, we will find the product value.
So, the values are $74 and 63.
Add 4200 + 240 + 210 + 12 = 4662
Hence the product of $74 and 63 is $4662.
Multiply.
Question 6.
Answer: 1128
Explanation: Given that, the values are 47 and 24.
Now, we will find the product value.
So, the values are 47 and 24.
Hence, the final product value is 1128.
Question 7.
Answer: 2944
Explanation: Given that, the values are 64 and 46.
Now, we will find the product value.
So, the values are 64 and 46.
Thus, the product of 64 and 46 is 2944.
Question 8.
83 × 67 = ____
Answer: 5561
Explanation: Given that, the values are 83 and 67.
Now, we will find the product value.
So, the values are 83 and 67.
Hence, the product of the given values is 5561.
Question 9.
91 × 78 = ____
Answer: 7098
Explanation: Given that, the values are 91 and 78.
Now, we will find the product value.
So, the values are 91 and 78.
Hence, the product value is 7098.
Problem Solving
Question 10.
A greyhound dog can jump a distance of 27 feet. How many feet will the greyhound travel if it jumps 12 times?
Answer: 324 feet the greyhound traveled.
Explanation: Given that,
A greyhound dog can jump a distance of 27 feet.
Now, we have to find out how many feet will the greyhound travel if it jumps 12 times.
So, multiply 12 by 27 we get the value.
Therefore, 324 feet the greyhound traveled.
Question 11.
The fourth-grade students at Tremont School received a ribbon if they read 50 books during the school year. The school gave out 69 ribbons at the end of the year. How many books did the students read in all?
Answer: 3450 books the students read in all.
Explanation: Given that,
The fourth-grade students at Tremont School received a ribbon if they read 50 books during the school year.
The school gave out 69 ribbons at the end of the year.
Now, we will find out how many books the students read in all.
So, the values are 69 and 50. Multiply it.
Therefore, 3450 books the students read in all.
Question 12.
Mathematical PRACTICE 2 Use Symbols Each day, enough paper is recycled in the United States to fill 15 miles of train boxcars. How many miles of boxcars could be filled in 5 weeks? Complete the equation to help you solve the problem.
15 × 5 × ___ = b
Answer: 15 x 5 x 7 = b
15 x 5 x 7 = 525 miles. So, 525 miles of boxcars could be filled in 5 weeks.
Explanation: Given that, the data is,
Each day, enough paper is recycled in the United States to fill 15 miles of train boxcars.
Now, we need to find out how many miles of boxcars could be filled in 5 weeks.
First, complete the equation it helps to solve the problem.
The week has 7 days. So the equation is 15 x 5 x 7.
Now, the product value is 15 x 5 x 7 = 525.
Hence, 525 miles of boxcars could be filled in 5 weeks.
HOT Problems
Question 13.
Mathematical PRACTICE 3 Which One Doesn’t Belong? Circle the multiplication problem that does not belong with the other three. Explain.
Answer: 37 x 18 does not belong because it is the only problem whose product does not have a zero in the one’s place. 35 x 18 does have a zero in the one’s place.
Explanation: Given that,
The value is 22 x 15, $45 x 28, 37 x 18, and $66 x 25.
Now, we will find the product value and find which value does not belong with the other three.
The product of 22 x 15 = 330.
The product of $45 x 28 = 1260.
The product of 37 x 18 = 666.
The product of $66 x 25 = 1650.
Based on the product value 37 x 18 does not belong to the other three.
Question 14.
? Building on the Essential Question Why can’t the product of two 2-digit numbers ever be two digits? Explain.
Answer: The least product of two 2-digit factors is 100, which is a result of multiplying 10 x 10, it is a least 2-digit factors. So, the product of two 2-digit numbers is never two digits.
McGraw Hill My Math Grade 4 Chapter 5 Lesson 4 My Homework Answer Key
Multiply.
Question 1.
Answer: 910
Explanation: Given that, the values are 26 and 35.
Now, we will find the product value.
So, the values are 26 and 35.
Hence, the product value is 910.
Question 2.
Answer: $1610
Explanation: Given that, the values are 46 and 35.
Now, we will find the product value.
So, the values are 46 and 35.
Therefore, the product value is $1610.
Question 3.
Answer: 5767
Explanation: Given that, the values are 79 and 73.
Now, we will find the product value.
So, the values are 79 and 73.
Hence, the product of the given values is 5767.
Question 4.
Answer: 3723
Explanation: Given that, the values are 73 and 51.
Now, we will find the product value.
So, the values are 73 and 51.
Hence, the product value is 3723.
Question 5.
Answer: 2773
Explanation: Given that, the values are 59 and 47.
Now, we will find the product value.
So, the values are 59 and 47.
Therefore, the product value is 2773.
Question 6.
Answer: 5734
Explanation: Given that, the values are 94 and 61.
Now, we will find the product value.
So, the values are 94 and 61.
Therefore, the product value is 5734.
Multiply
Question 7.
Answer: 3828
Explanation: Explanation: Given that, the values are 44 and 87.
Now, we will find the product value.
So, the values are 44 and 87.
Hence, the product value of the given values is 3828.
Question 8.
Answer: 1694
Explanation: Given that, the values are 77 and 22.
Now, we will find the product value.
So, the values are 77 and 22.
Hence, the product of the given values is 1694.
Problem Solving
Question 9.
Mrs. Taylor gave each student 75 pieces of paper at the beginning of the school year. If there are 32 students in her class, how many pieces of paper did she give out altogether?
Answer: she gives 2400 pieces of paper altogether.
Explanation: Given that,
Mrs. Taylor gave each student 75 pieces of paper at the beginning of the school year.
If there are 32 students in her class.
Now, we will find out how many pieces of paper she gives out altogether.
So, the values are 75 and 32.
Hence, she gives 2400 paper of pieces altogether.
Question 10.
Mr. Matthews gives each of his 32 students 15 minutes to present a book report to the class. How many minutes will it take for all his students to present their reports?
Answer: 480 minutes will take for all of his students to present their reports.
Explanation: As given in the question,
Mr. Matthews gives each of his 32 students 15 minutes to present a book report to the class.
Now, we will find out how many minutes will it take for all of his students to present their reports.
So, the values are 32 and 15. Multiply it.
Therefore, 480 minutes will take for all of his students to present the reports.
Question 11.
Mathematical PRACTICE 2 Use Symbols George collects 25 baseball cards each month. How many cards will he have at the end of one year? Complete the equation to help you solve the problem.
25 × ____ = n
Answer: 300 cards will he have at the end of one year.
Explanation: As given in the question,
George collects 25 baseball cards each month.
Now, we will find out how many cards will he have at the end of one year.
First, complete the equation to help you solve the problem.
We know that one year = 12 months.
Then the equation is 25 x 12 =n.
So, multiply 25 by 12.
Therefore, 300 baseball cards for the end of one year.
Question 12.
The office building is 48 floors high. Each floor has 36 windows. How many windows does the building have in all?
Answer: The building there are 1728 windows.
Explanation: Given that,
The office building is 48 floors high.
Each floor has 36 windows.
Now, we will find out how many windows are in a building.
So, the values are 48 and 36. Multiply it.
Therefore, the 1728 windows are there in a building.
Test Practice
Question 13.
There are 26 rows of bleachers in the school gym. At the pep rally, there were 17 students sitting in each row. How many students were there in all?
A. 43 students
B. 182 students
C. 208 students
D. 442 students
Answer: Option D
Explanation: Given that,
There are 26 rows of bleachers in the school gym.
At the pep rally, there were 17 students sitting in each row.
Now, we will find out how many students were there in all.
So, the values are 26 and 17. Multiply it.
Hence, there are 442 students in all.