Three variables x, y and z take values 2, 3, 4 or 5 such that their values are always distinct. If M and N denote the largest pos…
Mental Ability & Logical Reasoning ·Previously asked in UPSC Civil Services Examination 2026
View the full solved paper: GS Paper II
Question
Three variables x, y and z take values 2, 3, 4 or 5 such that their values are always distinct. If M and N denote the largest possible value and the smallest possible value, respectively, for the expression (x × y) + z, then M − N is
- A. 11
- B. 12
- C. 13 (Correct answer)
- D. 14
Correct Answer
Option C — 13
Detailed Solution & Explanation
The correct answer is Option C (13).
Key Points
- x, y, z are distinct values from {2, 3, 4, 5} and we evaluate (x × y) + z.
- Maximum: take the two largest for the product, 4 × 5 = 20, plus the largest remaining distinct value z = 3 → 23.
- Minimum: take the two smallest, 2 × 3 = 6, plus the smallest remaining z = 4 → 10.
Additional Information
- M − N = 23 − 10 = 13, so Option C.