6th Grade Math Textbook, Progress

Multiply Fractions by Fractions

8-1

Ms. Amazing is a great magician.

She can take a red rope that is


^3

8


yd long and change 
^2

3


of it

into a blue rope. How long is the

blue part of the rope?

To find how long the blue part of the rope, n, is,

multiply: 


2

3 


3

8 
ydn.

To multiply a fraction by a fraction:


Multiply the numerators.

Then multiply the denominators.


Write the product in simplest form.

The blue part of the rope is 
^14 
yd long.

You can also use the greatest common factor

(GCF) to multiply a fraction by a fraction.


Divide anynumerator and

denominator by their GCF.


Multiply the numerators.

Then multiply the denominators.

The product will be in simplest form.

^23

^38

^23 
^38

^23

^38

264

2.^64 .
66 
^14

1 1


^23 

^38 

^23 

^38 


1 4


^11 
^14




1

4 

simplest form

GCF of 2 and 8: 2

GCF of 3 and 3: 3

simplest form

Study these examples.

2 1


 145 

^56 

 145 

^56 


3 3




2

3





1


 3 


2

9 

simplest form

1

8

2

3

2

8

4

8

6

8

3

8

0 5

8

7

8

8

8

Draw a diagram to illustrate .

Then write a multiplication sentence.

32 ^34  126 ^12

3

4

2 3 2 3 3 4

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