Question

The present ages of A and B are in the ratio 3 : 4. Twelve years ago, their ages were in the ratio 2 : 3. The sum of the present ages of A and B (in years) is:

• A. 60
• B. 84
• C. 48
• D. 72

Answer 1

Answer:

B. 84

Solution:

Given:

Present age ratio of A and B = 3 : 4

Ratio of age of A and B before 12 years = 2 : 3

Calculation:

Let the present age of A and B be 3x and 4x

⇒ $\frac{(3x-12)}{(4x-12)} = \frac{2}{3}$

⇒ 3× (3x - 12) = 2× (4x -12)

⇒ 9x - 36 = 8x - 24

⇒ 9x - 8x = 36 - 24

⇒ x = 12

The total present age is 4x + 3x

⇒ $7x =7\times{12} = 84$

∴ The total present age is 84years.