Aman’s age is three times his son’s age. Ten years ago he was five times his son’s age. Find their present ages.

Let the son’s age is x years. Then, Aman’s age is 3x years.

3x – 10 = 5 (x-10)

3x – 5x = -50 + 10

- 2x = -40

x = 20

thus, son’s age is 20 years and Aman’s age is 60.