Past 3× and future 2× around today: Five years ago Mayank's mother was three times as old as Mayank. Five years from now she will be twice his age. What is Mayank's present age?

Verbal Reasoning Problems on Ages Difficulty: Medium
Choose an option
  • A
    13 years
  • B
    15 years
  • C
    20 years
  • D
    30 years

Answer

Correct Answer: 15 years

Explanation

Introduction / Context:Two symmetric time conditions (−5 and +5) precisely fix the present ages. Translate to equations and solve.

Given Data / Assumptions:

  • M = mother's present age; m = Mayank's present age.
  • Five years ago: M − 5 = 3(m − 5).
  • Five years from now: M + 5 = 2(m + 5).

Concept / Approach:Solve the pair by expressing M from both equations and equating them.

Step-by-Step Solution:1) From past: M = 3m − 10.2) From future: M = 2m + 5.3) Equate: 3m − 10 = 2m + 5 ⇒ m = 15.4) Then M = 2m + 5 = 35.

Verification / Alternative check:Five years ago: 30 vs 10 → 3×. In five years: 40 vs 20 → 2×. Both conditions hold.

Why Other Options Are Wrong:They fail one of the two multiplicative checks upon substitution.

Common Pitfalls:Mishandling the ±5 shift on both ages; both change simultaneously.

Final Answer:15 years

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