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.

Answer:

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 = _____.

Answer:

Given that,

The hikers hiked for four hours.

Each hour, they saw 21 animals

So, 4 x 21 = 84.

**Talk About It**

Question 1.

Explain how to draw an area model to represent 2 × 15.

Answer:

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.

Answer:

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 = ____

Answer:

Multiplication of 3 with 22 then you get 66.

3 x 22 = 66.

The array of 3 x 22 is

Question 2.

2 × 41 = ___

Answer:

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 = ______

Answer:

The array of 31 x 3 is

Multiplication of 31 with 3 then you get 93.

31 x 3 = 93.

Question 4.

42 × 2 = ____

Answer:

The array of 42 x 2 is

Multiplication of 42 with 2 then you get 84.

42 x 2 = 84.

Question 5.

24 × 2 = ____

Answer:

The array of 24 x 2 is

Multiplication of 24 with 2 then you get 48.

24 x 2 = 48.

Question 6.

33 × 2 = ____

Answer:

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?

Answer:

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?

Answer:

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?

Answer:

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.

Answer:

Given that is 3 x 12.

The partial products of 3 x 12 is

3 x 10 = 30.

3 x 2 = 6.

Add the products 30 + 6 = 36.

Therefore the product is 36.