Question

Five years ago, the age of A was twice the age of B. After five years, their age would be in the ratio 3 ∶ 2. Their present ages are:
1. 15 years and 10 years
2. 45 years and 35 years
3. 19 years and 12 years
4. 25 years and 15 years

Answer 1

Correct Answer - Option 4 : 25 years and 15 years

Given:

Five years ago, the age of A was twice the age of B. After five years, their age would be in the ratio 3 ∶ 2. 

Concept used:

Ratio method

Calculation:

Let the age of A and B five years ago be x years.

Age of A was twice the age of B

Five years later the Age of A and B

⇒ A : B = 2x + 5 : x + 5

After five years the age would be in the ratio of 3 : 2

⇒ A : B 

⇒ \(\frac{{2x + 10}}{{x + 10}} = \frac{3}{2}\)

⇒ 4x + 20 = 3x + 30

⇒ x = 10

Age of A and B at present be

⇒ A : B = 25 : 15

∴ The age of A at present is 25 years and that of B is 15 years.