Question

A man is four times as old as his son. The difference between their ages is 36. Find the sum of their ages.

Answer 1

x = son's age
4x = man's age

4x - x = 36
3x = 36
x = 36/3
x = 12 son's age

12 * 4 = 48 man's age

48 + 12 = 60   ←  the sum of their ages