The age of Somu is one-third his father's. 9 years back he was one-fifth of his father's age. What is his persent age ?	Choose the correct choice from the following answers.
A) 11 B) 18 C) 14 D) 12 E) 10

Rationale: explanation : let somu ' s age be x and that of his father be 3 x . so , x - 9 = 3 x - 9 / 5 = x = 18 answer : option b
Answer: B