# McGraw Hill My Math Grade 4 Chapter 4 Lesson 4 Answer Key Use Models to Multiply

All the solutions provided in McGraw Hill Math Grade 4 Answer Key PDF Chapter 4 Lesson 4 Use Models to Multiply will give you a clear idea of the concepts.

## McGraw-Hill My Math Grade 4 Answer Key Chapter 4 Lesson 4 Use Models to Multiply

Draw It

The hiking club has 3 groups of hikers. Each group has 12 people. How many hikers are in the hiking club altogether?

Use an array to find 3 × 12.
1. Draw a rectangular array.
Separate 12 into ____ and ____.

2. Find the partial products.
3 × 10 =
3 × 2 =
3. Add the partial products.
+ =
3 × 12 = ____
So, there are ____ hikers in the hiking club.

Given that,
The hiking club has 3 groups of hikers.
Each group has 12 people.
The array is 3 × 12.

The partial products of 3 x 12 is
3 x 10 = 30.
3 x 2 = 6.
Add the partial products
30 + 6 = 36.
So, there are 36 hikers in the hiking club.

Try It

The hikers hiked for four hours. Each hour, they saw 21 animals. How many animals did they see in all?
Use an area model to find 4 × 21.

1. Draw an area model. Separate 21 into ___ and ____. Label the model.
2. Find the partial products.

3. Add the partial products.
So, 4 × 21 = _____.

Given that,
The hikers hiked for four hours.
Each hour, they saw 21 animals

So, 4 x 21 = 84.

Question 1.
Explain how to draw an area model to represent 2 × 15.
The area model of 2 x 15 is

Multiplication of 10 x 2 = 20.
Multiplication of 5 x 2 = 10
Known add the products.
20 + 10 = 30.
Therefore 2 x 15 = 30.

Question 2.
Mathematical PRACTICE 6 Explain to a Friend Explain to a friend how you would multiply 3 × 32.
Multiplication of 3 with 32 then you get 96.
3 x 32 = 96.
First multiply 3 x 2 = 6.
Then multiply 3 x 30 = 90.
Then add the two products that is 90 + 6 = 96.

### McGraw Hill My Math Grade 4 Chapter 4 Lesson 4 My Homework Answer Key

Practice

Draw an array or area model to solve.

Question 1.
3 × 22 = ____
Multiplication of 3 with 22 then you get 66.
3 x 22 = 66.
The array of 3 x 22 is

Question 2.
2 × 41 = ___
The array of 2 x 41 is

Multiplication of 2 with 41 then you get 82.
2 x 41 = 82.

Draw an array or area model to solve.

Question 3.
31 × 3 = ______
The array of 31 x 3 is

Multiplication of 31 with 3 then you get 93.
31 x 3 = 93.

Question 4.
42 × 2 = ____
The array of 42 x 2 is

Multiplication of 42 with 2 then you get 84.
42 x 2 = 84.

Question 5.
24 × 2 = ____
The array of 24 x 2 is

Multiplication of 24 with 2 then you get 48.
24 x 2 = 48.

Question 6.
33 × 2 = ____
The array of 33 x 2 is

Multiplication of 33 with 2 then you get 66.
33 x 2 = 66.

Problem Solving

Algebra Write an equation to solve.

Question 7.
Tyrone uses 2 cups of flour for each batch of cookies. How much flour will he need to make 31 batches of cookies?
Given that,
Tyrone uses 2 cups of flour for each batch of cookies.
For 31 batches of cookies is 2 x 31 = 62.
Therefore 62 flour will he need to make 31 batches of cookies.

Question 8.
Corinne’s puppy eats 3 meals a day. How many meals does the puppy eat in 32 days?
Given that,
Corinne’s puppy eats 3 meals a day.
The number of meals that puppy eat in 32 days is 3 x 32 = 96.
Therefore the Corinne’s puppy eats 96 meals in 32 days.

Question 9.
Mathematical PRACTICE 2 Use Symbols There are 3 shelves. Each shelf has 21 books. How many books are there in all?
Given that,
There are 3 shelves.
Each shelf has 21 books.
The total number of books are 3 x 21 = 63.
Therefore there are 63 books in 3 shelves.

Vocabulary Check

Question 10.
Show how you would use partial products to solve 3 × 12.