How can GCF help when simplifying a fraction?

1 Answer
Apr 4, 2016

Please see following example.

Explanation:

Let a fraction be #312/168#.

Normally, as numerator and denominator are even, we will divide each by #2# and then again check numerator and denominator and use divisibility rule to examine the number that can divide them further.

This will go on till they cannot be divided any further by a number other than #1#.

On the contrary if we take GCF of #312# and #168#, we can divide numerator and denominator by GCF and we will get simplified fraction. In above case, GCF is #24# and dividing by #24#, we get

#312/168=(13xx24)/(7xx24)=13/7#

In earlier method it would have been

#312/168=(2xx156)/(2xx84)=156/84=(2xx78)/(2xx42)=78/42#

= #(2xx39)/(2xx21)=39/21=(3xx13)/(3xx7)=13/7#