All the solutions provided inÂ **McGraw Hill My Math Grade 3 Answer Key PDF Chapter 13 Lesson 5 Tile Rectangles to Find Area **will give you a clear idea of the concepts.

## McGraw-Hill My Math Grade 3 Answer Key Chapter 13 Lesson 5 Tile Rectangles to Find Area

You can find the area of a rectangle on a grid by counting the number of unit squares. If a rectangle is not on a grid, you can find its area by tiling it.

The dimensions of a rectangle are its length and width.

**Draw It**

Find the area of the rectangle at the right by tiling it.

1. Tile the rectangle by separating the rectangle into unit squares. Draw unit squares on the rectangle so that the length of the rectangle is 8 unit squares and the width is 3 unit squares.

2. Count the total number of unit squares.

There are ______________ unit squares.

So, the area of the rectangle is ________________ square units.

Tiling the rectangle results in an array.

The array has ___________ rows and _____________ columns.

Find 3 Ă— 8. 3 Ă— 8 = _______________

What do you notice about the product of 3 Ă— 8 and the total number of unit squares tiled in the rectangle?

Answer:

There are 24 unit squares.

So, the area of the rectangle is 24 square units.

Tiling the rectangle results in an array.

The array has 3 rows and 8 columns.

Find 3 Ă— 8. 3 Ă— 8 = 24

They are same.

**Try It**

Find the area of the rectangle at the right by tiling it.

1. Tile the rectangle by separating the rectangle into unit squares. Draw unit squares on the rectangle so that the length of the rectangle is 6 unit squares and the width is 5 unit squares.

2. Count the total number of unit squares.

There are _____________ unit squares.

So, the area of the rectangle is ____________ square units.

Tiling the rectangle results in an array.

The array has _____________ rows and _____________ columns.

Find 5 Ă— 6. 5 Ă— 6 = _____________

What do you notice about the product of 5 Ă— 6 and the total number of unit squares tiled in the rectangle?

Answer:

There are 30 unit squares.

So, the area of the rectangle is 30 square units.

Tiling the rectangle results in an array.

The array has 5 rows and 6 columns.

Find 5 Ă— 6. 5 Ă— 6 = 30

They are same.

**Talk About It**

Question 1.

How do arrays help you model the area of rectangles?

Answer: When you draw the rows and columns, you can count the square units.

Question 2.

**Mathematical PRACTICE** Stop and Reflect How could you use the dimensions of a rectangle to find its area without tiling it?

Answer: You can use the formula

Area = length Ă— width

Question 3.

Use your answer from Exercise 2 to find the area of a rectangle with a length of 7 units and a width of 4 units.

Answer:

Area = length Ă— width

A = 7 Ă— 4 = 28 sq. units

**Practice It**

**Tile each rectangle to find its area. Draw unit squares on each rectangle.**

Question 4.

The area is ______________ square units.

Answer:

s = 6 units

Area = 6 Ă— 6

A = 36

The area is 36 square units.

Question 5.

The area is ______________ square units.

Answer:

l = 5 units

w = 4 units

A = 5 Ă— 4 = 20

The area is 20 square units.

Question 6.

The area is ______________ square units.

Answer:

l = 4 units

w = 8 units

A = 4 Ă— 8 = 32

The area is 32 square units

Question 7.

The area is ______________ square units.

Answer:

l = 3 units

w = 4 units

A = 3 Ă— 4 = 12

The area is 12 square units

**Algebra Find the area of each rectangle without tiling it. Write a multiplication equation.**

Question 8.

Answer:

l = 9 units

w = 4 units

A = 9 Ă— 4 = 36

The area is 36 square units

Question 9.

Answer:

l = 7 units

w = 6 units

A = 7 Ă— 6 = 42

The area is 42 square units

**Apply It**

**Algebra Write a multiplication equation to solve Exercises 10 and 11.**

Question 10.

Lucas built a sandbox for his younger brother. The length of the sandbox was 7 feet and the width was 5 feet. He placed the sandbox in the backyard. How much area of the backyard was taken tip by the sandbox?

Answer:

Given,

Lucas built a sandbox for his younger brother. The length of the sandbox was 7 feet and the width was 5 feet.

A = 7 Ă— 5

A = 35 sq. ft

Question 11.

Perry created a one-page greeting card for his mom. The greeting card had a length of 6 inches and a width of 3 inches. What is the area of the greeting card?

Answer:

Given,

Perry created a one-page greeting card for his mom. The greeting card had a length of 6 inches and a width of 3 inches.

A = 6 Ă— 3

A = 18 sq. inches

Question 12.

**Mathematical PRACTICE** Use Math Tools In the space at the right, draw and tile a rectangle to represent Exercise 11.

Answer:

3 Ă— 6 = 18

Question 13.

**Mathematical PRACTICE** Make Sense of Problems A rectangle has a length of 8 meters and a width of 3 meters. Describe two different rectangles that have the same area as this rectangle.

Answer:

Given,

A rectangle has a length of 8 meters and a width of 3 meters.

A = 8 Ă— 3 = 24

A = 3 Ă— 8 = 24

**Write About It**

Question 14.

How is the area of a rectangle related to the operation of multiplication?

Answer:

Area of a rectangle = length Ă—Â width

### McGraw Hill My Math Grade 3 Chapter 13 Lesson 5 My Homework Answer Key

**Practice**

**Tile each rectangle to find its area. Draw unit squares on each rectangle.**

Question 1.

The area is _______________ square units.

Answer:

A = 6 Ă— 4

A = 24 sq. units

The area is 24 square units.

Question 2.

The area is _______________ square units.

Answer:

A = 5 Ă— 3

A = 15 sq. units

The area is 15 square units.

**Algebra Find the area of each rectangle without tiling it. Write a multiplication equation.**

Question 3.

Answer:

A = 8 Ă— 7

A = 56 sq. units

The area is 56 square units.

Question 4.

Answer:

A = 3 Ă— 9

A = 27 sq. units

The area is 27 square units.

**Problem Solving**

**Algebra Write a multiplication equation to solve Exercises 5 and 6.**

Question 5.

A piece of poster board is in the shape of a rectangle. The length of the poster board is 2 feet and the width is one foot. What is the area of the piece of poster board?

Answer:

Given,

A piece of poster board is in the shape of a rectangle. The length of the poster board is 2 feet and the width is one foot.

A = 2 Ă— 1 = 2

Question 6.

**Mathematical PRACTICE** Model Math A rectangular garden has a length of 8 meters and a width of 5 meters. What is the area of the garden?

Answer:

Given,

A rectangular garden has a length of 8 meters and a width of 5 meters.

A = 8 Ă— 5 = 40 sq. meters

Question 7.

Circle the number sentence that correctly represents the area of a rectangle, in square inches, with a length of 4 inches and a width of 10 inches.

4 + 10 = 14

4 Ă— 10 = 40

4 + 10 + 4 + 10 = 28

Answer:

Given,

length = 4 inch

width = 10 inch

Area = 4 Ă— 10 = 40 sq. inch