Multiplying Simple Fractions with Reducing Across Fractions

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Example 1 Simple Fraction Multiplication with Reducing Across Fractions

5		1
---	x	---	=	---
4		5

Before multiplying the numerators and denominators, look for ways to reduce across both fractions. This is also called cancellation. This means to see if a numerator and a denominator can be divided by a common factor or reduced. In this example the 5 of the first numerator can be reduced with the 5 of the second denominator. The result is both numbers being changed to 1 as follows:

5/5		1
---	x	---	=	---
4		5/5

1		1		1
---	x	---	=	---
4		1		4

Then you will not have to reduce your answer.

The answer in simplest form is 1/4.

Example 2 Simple Fraction Multiplication with Reducing Across Fractions Several Times

2		9
---	x	---	=	---
3		18

Before multiplying the numerators and denominators, look for ways to reduce across both fractions. This means to see if a numerator and a denominator can be divided by a common factor or reduced. In this example the 2 of the first numerator can be reduced with the 18 of the second denominator. The result is:

2/2		9
---	x	---	=	---
3		18/2

The problem 2/3 times 9/18 becomes:

1		9
---	x	---	=	---
3		9

Look for other ways to reduce across both fractions. This means to see if a numerator and a denominator can be divided by a common factor or reduced. In this example the 3 of the first denominator can be reduced with the 9 of the second numerator. The result is:

1		9/3
---	x	---	=	---
3/3		9

The problem 1/3 times 9/9 now becomes:

1		3
---	x	---	=	---
1		9

You are not allowed to cancel two denominators with each other.

Look for another way to reduce across fractions. This means to see if a numerator and a denominator can be divided by a common factor or reduced. In this example the 3 of the second numerator can be reduced with the 9 of the second denominator. The result is:

1		3/3
---	x	---	=	---
1		9/3

The problem 1/1 times 3/9 now becomes:

1		1		1
---	x	---	=	---
1		3		3

After all of the reducing or cancelling the final answer is 1/3.

You will not have to reduce your answer since you cancelled out as much as possible.

The answer in simplest form is 1/3.