If a number is added to the numerator of 7/8, and the same number is subtracted from the denominator, the result is 2, find the number?

Question

If a number is added to the numerator of 7/8, and the same number is subtracted from the denominator, the result is 2, find the number?

Answer 1

7/8  8/7  9/6  10/5=2

Sometimes doing it is good. 

If you want to get complicated

(7+x)/(8-x) = 2

7+x=2(8-x)

7+x=16-2x

3x=9

x=3 which gives (7+3)/(8-3) = 10/5 = 2