Grade 4 - Progress in Mathematics

Update your skills. See page 12.

Relate Multiplication and Division

5-2

Division and multiplication are inverse operations.

Division “undoes” multiplication and

multiplication “undoes” division.

Find the related multiplication fact for 36 
 9 4.

To find the related multiplication fact,

first think about what each number

in the division fact represents.

36 
 9  4

number

in all

number

in all

number

in each

group

number

in each

group

number

of

groups

number

of

groups

6  7  42

42 
 7  6 or

So, 42 
 7 6 is the related

division fact for 6  7 42.

groups in each in all

6

7 
 4  2 

in each

groups

in all

Then think about the meaning of multiplication.

So, 4  9 36 is the related multiplication fact for 36 
 9 4.

4  9  36

Study this example.

Think

Multiplying 9 “undoes”

dividing by 9.

Think

Dividing by 7

“undoes”

multiplying 7.

3.2

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