Minimalist IAS
CSAT 2020 paper

UPSC CSE CSAT 2020 · Question 20 · Puzzles, arrangements & general mental ability

If in a particular year 12th January is a Sunday, then which one of the following is correct?

If in a particular year 12th January is a Sunday, then which one of the following is correct?

Answer & explanation

Answer: (c) 12th July is a Sunday if the year is a leap year.

From 12 January to 12 July is 181 days in an ordinary year and 182 days in a leap year. 182 is exactly 26 weeks, so in a leap year 12 July falls on the same day, Sunday.

  1. Days from 12 January to 12 July: January 31, February 28 or 29, March 31, April 30, May 31, June 30.
  2. Ordinary year: 181 days = 25 weeks + 6 days, so 12 July is Saturday.
  3. Leap year: 182 days = 26 weeks exactly, so 12 July is Sunday.
  4. 15 July is then Tuesday (ordinary year) or Wednesday (leap year), never Sunday — (a), (b) and (d) fail.

Remember · Count days between the two dates and divide by 7; the remainder is the number of weekdays to move forward.

Question and answer: UPSC's official GS Paper II (2020, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). ·

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