Question
The ratio of the present age of a father to his son is
5:2. After 8 years, the ratio will be 3:2. What is the present age difference between them?Solution
Let present ages of father and son be ‘5x’ years and ‘2x’ years, respectively. ATQ: (5x + 8)/(2x + 8) = 3/2 ⇒ 2(5x + 8) = 3(2x + 8) ⇒ 10x + 16 = 6x + 24 ⇒ 4x = 8 ⇒ x = 2 Desired difference = 5x – 2x = 3x = 3 × 2 = 6 years
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