Let Aman's present age be 'x' years.
Then his mother's present age = 3x
After 9 years, their ages are x + 9 and 3x + 9
Given that,
(x + 9) + (3x + 9) = 70
⇒ 4x + 18 = 70
⇒ 4x = 52
⇒ x = 13
Thus, Aman's present age is 13 years and his mother's age is 3 times 13 = 39 years.