Ram and Shyam work on a job together for four days and complete 60% of it. Ram takes leave then and Shyam works for eight more days to complete the job. How long would Ram take to complete the entire job alone?
Answer & explanation
Answer: (c) 10 days
Together they do 60% in 4 days, i.e. 15% a day. Shyam alone does the other 40% in 8 days, i.e. 5% a day. So Ram does 10% a day and would need 10 days alone.
- Together: 60% in 4 days = 15% a day.
- Shyam alone: 40% in 8 days = 5% a day.
- Ram = 15% − 5% = 10% a day, so 100 ÷ 10 = 10 days.
Remember · Turn work into per-day percentages; rates simply add when people work together.
Question and answer: UPSC's official GS Paper II (2016, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). ·