Minimalist IAS
CSAT 2025 paper

UPSC CSE CSAT 2025 · Question 77 · Number system

Consider a set of 11 numbers: Minimum value of the average of the numbers of the set when they are…

CSAT 2025 · Q77

Number system Easy

Consider a set of 11 numbers:

  1. Value-I: Minimum value of the average of the numbers of the set when they are consecutive integers ≥ −5.
  2. Value-II: Minimum value of the product of the numbers of the set when they are consecutive non-negative integers.

Which one of the following is correct?

Answer & explanation

Answer: (c) Value-I = Value-II

The lowest allowed set, −5 to 5, is balanced around 0, so its average is 0. The product of 0, 1, …, 10 is 0, the smallest possible for non-negative integers. Both values are 0.

  1. Value-I: the lowest possible set is −5, −4, …, 4, 5. Its average is 0; any later set has a larger average. So Value-I = 0.
  2. Value-II: the set 0, 1, …, 10 has product 0; any set starting above 0 has a positive product. So Value-II = 0.
  3. Value-I = Value-II.

Remember · Consecutive integers balanced around 0 average 0; a product of non-negative numbers is smallest (0) when it includes 0.

Question and answer: UPSC's official GS Paper II (2025, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). ·

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