Rohit tells his son, "I was three times of your present age when you were born." If Rohit's present age is 48 years, how old was the boy 4 years ago?

Given:

Rohit's present age = 48 years

Rohit says, "I was three times of your present age when you were born."

Formula used:

Rohit's age when the boy was born = 3 × boy's present age

Boy's present age = Rohit's present age - Rohit's age when the boy was born

Boy's age 4 years ago = Boy's present age - 4

Calculations:

Let boy's present age be x.

⇒ Rohit's age when the boy was born = 3 × x

⇒ Rohit's present age = Rohit's age when the boy was born + x

⇒ 48 = 3 × x + x

⇒ 48 = 4 × x

⇒ x = 12

Boy's present age = 12 years

Boy's age 4 years ago = 12 - 4

⇒ Boy's age 4 years ago = 8

∴ The correct answer is option (2).