The ratio of the ages of father and son now is 6 : 1. After 5 years the ratio will become 7 : 2. What is the sum of their ages now?

Question: The ratio of the ages of father and son now is 6 : 1. After 5 years the ratio will become 7 : 2. What is the sum of their ages now?

Solution:
Let, the ages of the father = 6x
and the ages of the son = x

ATQ,
(6x + 5) / (x +5) = 7/2
⇒ 12x + 10 = 7x + 35
⇒ 5x = 25
⇒ x = 5

So, the ages of the son = 5 years
and the ages of the father = 6 × 5 = 30 years

∴ the sum of their ages now = 30 + 5 = 35 years