Twelve years ago, Babu was twice as old as Vuttu. If the ratio of their present ages is 4 : 3 respectively, find the difference between their present ages.

Question: Twelve years ago, Babu was twice as old as Vuttu. If the ratio of their present ages is 4 : 3 respectively, find the difference between their present ages.

Solution:
Let 12 years ago age of Vuttu was x years and age of Babu was 2x.
So, present age of Vuttu = x + 12
And, present age of Babu = 2x + 12

As per question,
(2x + 12)/(x + 12) = 4/3
⇒ 6x + 36 = 4x + 48
⇒ 2x = 12
∴ x = 6

Present age of Vuttu = 6 + 12 = 18 years
Present age of Babu = 2 × 6 + 12 = 24 years

∴ Required difference between their ages = 24 - 18 = 6 years