Question

A boy is 42 years younger than his father .In 8 years' times , he will be 1/4 times as old as his father .Find their present ages.

Answer 1

now:
father ---- x
son ------ x - 42

in 8 years:
father = x+8
son = x-42 + 8 = x - 34

x - 34 = (1/4)(x + 8)
x - 34 = x/4 + 2
each term times 4
4x - 136 = x + 8
3x = 144
x = 48

The father is now 48 and the son is now 6

check:
in 8 years, dad will be 56
son will be 14, and 14 is 1/4 of 56
All is good!