We included **HMH Into Math Grade 3 Answer Key**** PDF** **Module 1 Lesson 3 Represent Multiplication with Arrays**Â to make students experts in learning maths.

## HMH Into Math Grade 3 Module 1 Lesson 3 Answer Key Represent Multiplication with Arrays

I Can use arrays to represent problems about equal groups and to write multiplication equations.

**Spark Your Learning**

Sahil’s class is planning a show. Help his class decide how to arrange chairs for the family members. Choose any number of rows. Each row will have 8 chairs. How many chairs will be needed for the family members?

**Show your thinking.**

There are ___ rows with ___ chairs in each row.

___ chairs will be needed for the family members.

Answer:

Explanation:

Sahil’s class is planning a show

Help his class decide how to arrange chairs for the family members

Choose any number of rows

Each row will have 8 chairs

I chose 5 number of rows

There are 5 rows with 8 chairs in each row

5 x 8 = 40

So, 40 chairs will be needed for the family members.

**Turn and Talk** Describe your representation. What shape does it look like? How does your arrangement help to find the total number of chairs?

**Build Understanding**

1. Sahil’s class is arranging chairs for another show. This time, each row has 9 chairs. There are 3 rows. How many chairs are there?

Use tiles to show equal groups.

A. How many tiles will you put in each row? ____

How many rows will you make? _____

B. What multiplication equation can you write to solve this problem?

Answer:

Explanation:

Sahil’s class is arranging chairs for another show

This time, each row has 9 chairs

There are 3 rows

So, 3 x 9 = 27

Therefore, there are 27 chairs in all.

**Connect to Vocabulary**

You previously learned about equal groups of objects. Equal groups of objects can be arranged in an array. An array is a set of objects arranged in rows and columns.

C. Describe what each factor and the product model in the multiplication equation for the array.

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D. How many chairs are there? __________

Answer:

The rows in the array is the multiplier

The columns in the array are multiplicands

The product is the answer

3 rows of 9 columns

So, 3 x 9 = 27

Therefore, there are 27 chairs in all.

**Turn and Talk** How would a 3 Ă— 9 array be different from a 9 Ă— 3 array?

Answer:

A 3 x 9 array has 3 rows of 9 columns and a 9 x 3 array will have 9 rows of 3 columns

So, the number of rows and columns are different in both the arrays.

2. Morgan’s class needs to arrange 12 chairs into 2 or more equal rows for a concert. What are all the ways the chairs can be arranged?

Show each array. Label the number of rows and number of tiles in each row.

A. What multiplication equations can you write to model the arrays?

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Answer:

Explanation:

Morgan’s class needs to arrange 12 chairs into 2 or more equal rows for a concert

I made 3 rows of 4 chairs

3 x 4 = 12

So, the equation that models the array is 3 x 4 = 12.

**Turn and Talk** What patterns do you see in the arrays?

Answer:

In the arrays the number of rows and columns will increase or decrease with the increase or decrease with the numbers.

**Check Understanding Math Board**

Question 1.

The chairs are arranged in 3 rows. Each row has 5 chairs. Make an array for the problem. Write a multiplication equation. How many chairs are there?

Answer:

Explanation:

The chairs are arranged in 3 rows

Each row has 5 chairs

The multiplication equation is 3 x 5 = 15

So, there are 15 chairs.

**On Your Own**

Question 2.

**Model with Mathematics** Marco paints lines on the ground of a playground for a game. Each row has 4 squares. There are 8 rows.

- Make an array for the problem. Describe your array.

_______________________________ - Write a multiplication equation for the problem. How many squares are there?

_______________________________

Answer:

Explanation:

Marco paints lines on the ground of a playground for a game

Each row has 4 squares

There are 8 rows

I drew an array using squares

There are 8 rows and 4 coulumns

The multiplication equation is 8 x 4 = 36

So, there are 36 squares in all.

Question 3.

**Attend to Precision** Gwen-places playing cards in a 6 Ă— 7 rectangular arrangement. How might you describe the arrangement of Gwen’s cards? How many cards does Gwen arrange?

Answer:

Explanation:

Gwen-places playing cards in a 6 Ă— 7 rectangular arrangement

There are 6 rows and 7 columns

So, 6 x 7 = 42

Therefore, Gwen arranged 42 cards in all.

Question 4.

**STEM** Solar cells on a solar panel collect sunlight which is changed into electricity. Solar cells are arranged in equal rows on a frame to make a solar panel. Describe one way you could arrange 24 solar cells in an array to make a panel.

Answer:

Explanation:

Solar cells on a solar panel collect sunlight which is changed into electricity

Solar cells are arranged in equal rows on a frame to make a solar panel

I arranged 24 solar cells in an array to make a panel

I made an array of 4 rows and 6 columns

4 x 6 = 24.

**I’m in a Learning Mindset!**

How effective was making an array for understanding multiplication?

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