If 7 24 = 25 and 12 16 = 20, then what is 16 63 equal to?

Mental Ability & Logical Reasoning ·Previously asked in UPSC Civil Services Examination 2025

View the full solved paper: GS Paper II

Question

If 7 24 = 25 and 12 16 = 20, then what is 16 63 equal to?

  1. A. 70
  2. B. 66
  3. C. 65 (Correct answer)
  4. D. 64

Correct Answer

Option C — 65

Detailed Solution & Explanation

The correct answer is 65.

Key Points

  • Pattern: 7² + 24² = 49 + 576 = 625 = 25² and 12² + 16² = 144 + 256 = 400 = 20².
  • These are Pythagorean triples.
  • 16² + 63² = 256 + 3969 = 4225 = 65². Answer: 65.