Q. A completes a task in 15 days. B starts helping him on the 6th day and the work finishes in 10 days. In how many days can B alone finish the work?
✅ Correct Answer: (C)
30 days
Explanation: A works 5 days → 5/15 = 1/3. Remaining 2/3 completed in 5 days by A+B. A = 1/15, so B = 2/3 ÷ 5 - 1/15 = 1/30.
Explanation by: Kartik Sharma
A works 5 days → 5/15 = 1/3. Remaining 2/3 completed in 5 days by A+B. A = 1/15, so B = 2/3 ÷ 5 - 1/15 = 1/30.