Joseph visits the club on every 5th day, Harsh visits on every 24th day, while Sumit visits on every 9th day. If all three of them met at the club on a Sunday, then on which day will all three of them meet again?
Answer & explanation
Answer: (b) Wednesday
All three meet again after LCM(5, 24, 9) = 360 days. That is 51 weeks and 3 days, so the meeting falls three days after Sunday — on Wednesday.
- They meet together again after LCM(5, 24, 9) days.
- 24 = 2³ × 3 and 9 = 3², so LCM = 2³ × 3² × 5 = 360.
- 360 = 7 × 51 + 3, so the weekday moves on by 3 days.
- Sunday + 3 days = Wednesday.
Remember · Next joint meeting = LCM of the intervals; the weekday shifts by (LCM mod 7).
Question and answer: UPSC's official GS Paper II (2021, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). ·