A father is three times as old his son. Eight years ago, the father was five times as old as his son. What is the present age of the son ?

Suppose the present age of the son is x years.

Therefore, the present age of father will be 3x

years.

According to question,

5(x – 8) = 3x – 8

⇒ 5x – 40 = 3x – 8

⇒ 5x – 3x = 40 – 8

⇒ 2x = 32

$herefore x=frac{32}{2}=16$ years