A father was 12 times as old as his son 20 years back. Now he is twice as old as his son. What are their present ages?

Suppose the present age of son = P years The present age of father = 2P years According to question , 20 years ago , (2P – 20) = 12 (P – 20) ⇒ 2P – 20 = 12P – 240 ⇒ 12P – 2P = 240 – 20 ⇒ 10P = 220 ∴ P = 22 years Age of father = 2P = 2 x 22 = 44 years