A’s present age is one fourth of his mother’s age two years ago. A’s mother’s age is twice of B’s age after 10 years. If B’s 12th birthday was celebrated 4 years ago, then what is A’s present age ?

A’s present age is one fourth of his mother’s age two years ago. A’s mother’s age is twice of B’s age after 10 years. If B’s 12th birthday was celebrated 4 years ago, then what is A’s present age ? Correct Answer 10 years

Given:

A’s age = 1 / 4 ( Mother’s age two years ago)

A’s Mother’s age = 2 × (B’s age after 10 years)

B’s 12^th birthday was 4 years ago

Concept:

4 years ago B’s age was 12. So present age of B is 16

Explanation:

Let’s denote A’s mother’s age as M

⇒ A = 1 / 4 (M – 2)

And, M + 10 = 2 × (B +10)

B = 16 (∵ 4 years ago B’s age was 12)

Calculation:

 M + 10 = 2 × (16 + 10)

⇒ M = 42

We have, A = 1 /4 (M – 2)

⇒ A = 1 / 4 (42 – 2) = 10

∴ Present age of A = 10