Siblings with fixed gap – Nikhil is 8 years younger than Rohan. How old will Rohan be when he is exactly twice as old as Nikhil?

Introduction / Context:
We are asked for the age Rohan will be at the moment he is twice Nikhil, given a constant present gap. Modeling “t years from now” for both brothers and equating produces a single linear equation in t that directly yields Rohan’s target age.

Given Data / Assumptions:

• Nikhil = Rohan − 8 (present ages).
• We want t such that Rohan + t = 2(Nikhil + t).

Concept / Approach:
Substitute Nikhil in terms of Rohan, solve for the calendar time t, then compute Rohan’s age at that time.

Step-by-Step Solution:
R + t = 2((R − 8) + t) = 2R − 16 + 2t.Bring terms together: R + t − 2R + 16 − 2t = 0 ⇒ −R − t + 16 = 0 ⇒ R + t = 16.Therefore, when the condition holds, Rohan will be 16 years old.

Verification / Alternative check:
If Rohan is 16, Nikhil is 8 (because the gap is 8). 16 = 2 × 8, so the condition is satisfied.

Why Other Options Are Wrong:
They do not meet the 2× condition alongside the fixed 8-year gap.

Common Pitfalls:
Solving for t and reporting t instead of Rohan’s age at that time. The question explicitly asks for Rohan’s age.

Final Answer:
16 years