Question

Three years  ago, the ratio of Sonu’s age and Monu’s age was 4 ∶ 5 and three years later, ratio of their ages will be 5 ∶ 6. Find the present age of Monu.

1. 30 years
2.  32 years
3. 33 years
4. 35 years
5. 28 years

Answer 1

Correct Answer - Option 3 : 33 years

Given:

Three years ago, the ratio of Sonu’s age and Monu’s age = 4∶ 5

Three years later, the ratio of their ages = 5 ∶ 6.

Concept Used:

Ratio using.

Calculation:

Let Sonu’s age and Monu’s age three years ago be 4x and 5x .

Then present age of Sonu = 4x + 3

Present age of Monu = 5x + 3

Three years later,

Sonu’s age = 4x + 3 + 3 = 4x + 6

Monu’s age = 5x + 3 + 3 = 5x + 6

According To Question,

{(4x + 6)/(5x + 6)} = 5/6

⇒ 6(4x + 6) = 5(5x + 6)

⇒ 24x + 36 = 25x + 30

⇒ 25x – 24x = 36 – 30

⇒ x = 6 years

So, Present age of Monu = 5x + 3 = 5 × 6 + 3 = 33 years

∴ Present age of Monu is 33 years old.