# McGraw Hill My Math Grade 3 Chapter 13 Answer Key Perimeter and Area

All the solutions provided inÂ McGraw Hill My Math Grade 3 Answer Key PDF Chapter 13 Perimeter and Area will give you a clear idea of the concepts.

## McGraw-Hill My Math Grade 3 Answer Key Chapter 13 Perimeter and Area

Essential Question

How are perimeter and area related and how are they different?
Answer: Perimeter is the distance around the outside of a shape. The area measures the space inside a shape.

Question 1.
3 + 4 + 3 + 4 = ___________
3 + 4 + 3 + 4
2(3 + 4) = 2(7) = 14

Question 2.
5 + 6 + 5 + 6 = ____________
5 + 6 + 5 + 6
2(5 + 6)
2(11) = 22

Question 3.
17 + 20 + 31 = _____________
17 + 20 + 31 = 68
The sum of three numbers 17, 20 and 31 is 68.

Question 4.
40 + 63 + 12 = _____________
40 + 63 + 12 = 115
The sum of three numbers 40, 63 and 12 is 115.

Question 5.
From his house, Marcus walked three blocks north to the grocery store, six blocks east to the library, three blocks south to the park, and six blocks west back to his house. How many blocks did he walk in all?
Given,
Marcus walked three blocks north to the grocery store, six blocks east to the library, three blocks south to the park, and six blocks west back to his house.
6 + 3 + 6 = 15
Thus he walked 15 blocks in all.

Multiply.

Question 6.
3 Ă— 5 = ____________
By multiplying 3 and 5 we get 15.

Question 7.
1 Ă— 7 = _____________
By multiplying 1 and 7 we get 7.

Question 8.
4 Ă— 6 = ____________
By multiplying 4 and 6 we get 24.

Question 9.
5 Ă— 10 = _____________
By multiplying 5 and 10 we get 50.

Question 10.
8 Ă— 9 = _____________
By multiplying 8 and 9 we get 72.

Question 11.
6 Ă— 5 = ____________
By multiplying 6 and 5 we get 30.

Question 12.
Write a multiplication sentence that represents the array shown at the right.

There are 3 rows and 7 columns.
So, the multiplication is 3 Ă— 7 = 21.

Review Vocabulary

decompose
Distributive Property

Making Connections
Use the review vocabulary to help you complete each section of the chart. Then answer the question.

Explain how you used the Distributive Property to model 8 Ă— 5.
8 Ă— 5 = (4 Ă— 5) + (4 Ă— 5)
= 20 + 20
= 40

My Vocabulary Cards

Ideas for Use

• Group 2 or 3 common words. Add a word that is unrelated to the group. Then work with a friend to name the unrelated word.
• Use the blank cards to draw or write examples that will help you with concepts like relating area to multiplication and addition.

A figure made up of two or more figures.
Composite comes from the root word compose, meaning â€śto put together.â€ť tise compose to write a sentence that describes the figure on this card.
A figure made up of two or more figures is called a composite figure.

The number of square units needed to cover a figure without overlapping.
What is a real-life example of a situation when you would need to find area?
The real-life example of a situation to find the area is football field.
(or)
Painting the gable end of a barn.

The distance around the outside of a figure.
The prefix peri- means â€śall around.â€ť How does this help you remember the definition of perimeter?
Answer: Perimeter is nothing but adding all the sides of the figure.

An equation that shows the relationship between two or more quantities.
Explain why formulas are helpful to use when finding area.
The formulas are helpful to find the product of two or more quantities.

A square with a side length of one unit
A friend tells you he measured his bedroomâ€™s perimeter in unit squares. Why is he incorrect?
Answer: No the units of the perimeter cannot be measured in square units.

A unit for measuring area.
Draw a rectangle that has a length of 6 square units and a width of 4 square units.