A age 10 years later from now will be thrice as old as B was 10 years…

The correct answer is Option (3) → 23 years

Given:

• A's age 10 years later = A + 10

• B's age 10 years ago = B − 10

• A + 10 = 3 × (B − 10) → (Equation 1)

Also:

• A is 6 years older than B → A = B + 6 → (Equation 2)

Step 1: Substitute Equation 2 into Equation 1

From Equation 1:
A + 10 = 3 × (B − 10)

Substitute A = B + 6:
(B + 6) + 10 = 3 × (B − 10)
⇒ B + 16 = 3B − 30
⇒ 16 + 30 = 3B − B
⇒ 46 = 2B
⇒ B = 23

Present age of B is: 23 years