A fraction becomes 45 when 1 is added to each numerator and denominator. However, if we subtract 5 from each then it becomes 12. Find the fraction.
Let the numerator be x and the denominator be y
(x+1)(y+1) = 45
5(x + 1) = 4(y + 1)
5 x + 1 = 4y .................... (1)
(x−5)(y−5) = 12
y = 2x - 5 ................. (2)
On solving, x = 7 and y = 9