All the solutions provided in McGraw Hill My Math Grade 3 Answer Key PDF Chapter 8 Review will give you a clear idea of the concepts.

Vocabulary Check

Use the clues and the word bank below to solve the puzzle.

Commutative known facts pattern related facts

Across
1. The 11 s facts show a ____. When a single digit number is multiplied by 11, the product is the digit repeated.
2. Basic facts using the same three numbers. Sometimes called a fact family.

Down
3. Facts which you have memorized.
4. The property of multiplication which states that the order in which two numbers are multiplied does not change the product.

Concept Check

Algebra Use the inverse operation to find each unknown.

Question 5.
30 ÷ 6 =
6 × = 30
The unknown is _____.
30 divided by 6 equal to 5.
30 ÷ 6 = 5.
The inverse operation is
Multiplication of 6 with 5 then you get 30.
6 x 5 = 30.
The unknown is 5.

Question 6.
28 ÷ 7 =
7 × = 28
The unknown is _____.
28 divided by 7 equal to 4.
28 ÷ 7 = 4.
The inverse operation is
Multiplication of 7 with 4 then you get28.
7 x 4 = 28.
Therefore the unknown is 4.

Question 7.
48 ÷ 6 =
6 × = 48
The unknown is _____.
48 divided by 6 equal to 8.
48 ÷ 6 = 8.
The inverse operation is.
Multiplication of 6 with 8 then you get 48.
6 x 8 = 48.
Therefore the unknown is 8.

Double a known fact to find each product. Draw an array.

Question 8.
8 × 7 = ____
4 × 7 = ___
____ × ___ = ____
28 + ____ = ____
Multiplication of 8 with 7 then you get 56.
8 x 7 = 56.
4 x 7 = 28.
Double the known fact is
4 x 7 + 4 x 7 = 8 x 7.
28 + 28 = 56.
The array of 8 x 7 is

Question 9.
6 × 9 = ___
Multiplication of 6 with 9 then you get 52.
6 x 9 = 54.
Double the known fact is
6 x 9 + 6 x 9 = 12 x 9
12 x 9 = 108.
Double the product is
54 + 54 = 108.
The array of 6 x 9 is

Write an addition sentence and a multiplication sentence for each.

Question 10.
5 rows of 11 counters ___ + ___ + ___ + ___ + ___ = ____
___ × ___ = ____
Given that,
5 rows of 11 counters.
So, 5 x 11 = 55.
The addition sentence is 11 + 11 + 11 + 11 + 11 = 55.

Question 11.
6 rows of 12 counters ___ + ___ + ___ + ___ + ___ + ___ = ____
___ × ___ = ____
Given that,
6 rows of 12 counters.
So, 6 x 12 = 72.
The addition sentence is 12 + 12 + 12 + 12 + 12 + 12 = 72.

Question 12.
3 rows of 8 counters ___ + ____ + ____ = ____
___ × ___ = ____
Given that,
3 rows of 8 counters
So, 3 x 8 = 24.
The addition sentence is 8 + 8 + 8 = 24.

Question 13.
7 rows of 11 counters ___ + ___ + ___ + ___ + ___ + ___ + ___ = ____
___ × ___ = ____
Given that,
7 rows of 11 counters.
So, 7 x 11 = 77.
The addition sentence 11 + 11 + 11 + 11 + 11 + 11 + 11 = 77.

Problem Solving

Question 14.
Bev notices this heart-shaped button has 4 holes. She needs 11 of these buttons for a project. How many button holes will there be altogether? Write a multiplication sentence to solve.

Given that,
The heart shaped button has 4 holes.
She needs 11 of these buttons for a project.
The multiplication sentence is 4 x 11 = 44.
Therefore the  total number of buttons are 44.

Question 15.
The array is a model for 5 × 9 = 45. Write the division sentence that is modeled by the array.
Multiplication of 5 with 9 then you get 45.
5 x 9 = 45.
The inverse of 5 x 6 = 45 is
45 divided by 5 equal to 9.
45 ÷ 5 = 9.

Question 16.
Chandler works 4 hours each week. How many weeks will it take him to work 36 hours? Write a division sentence to solve.
Given that,
Chandler works 4 hours each week.
The number of weeks will it take him to work 36 hours.
The division sentence is 36 ÷ 4 = 9.
Therefore there are 9 weeks to take him to work 36 hours.

Question 17.
Mrs. King took 12 crates packed with lunch boxes on a field trip. Each crate had 6 lunch boxes inside. How many lunch boxes were there altogether? Write a multiplication sentence to solve.
Given that,
Mrs. King took 12 crates packed with lunch boxes on a field trip.
Each crate had 6 lunch boxes inside.
The multiplication sentence is
12 x 6 = 72.
Therefore there are 72 lunch boxes.

Test Practice

Question 18.
How much will these 4 paperback books cost altogether?

A. $7 B.$14
C. $21 D.$28
Given that,
There are 4 paperback books.
The cost of each book is $7. The cost of 4 paperback books are$7 + $7 +$7 + $7 =$28.
Option D is the correct answer.

Reflect

Use what you learned about multiplication and division to complete the graphic organizer.