If the fraction is equal to 3/4, what is the denominator of this fraction?

Question

The numerator of a certain fraction is 5 less than the denominator.

 

Please help. Thank you

Answer 1

Let x = denominator

 

Then, x - 5 = numerator

 

So, (x - 5)/x = 3/4

 

Cross multiply to get 4(x - 5) = 3x

 

                                     4x - 20 = 3x

 

                                               x = 20

 

The fraction is 15/20