Q. Pipe A fills a tank in 6 hours, pipe B in 12 hours. After 3 hours, pipe A is closed. How long will pipe B take to fill the remaining tank?
✅ Correct Answer: (B)
3 hours
Explanation: Work done in 3 hrs = 3(1/6+1/12)=3/4. Remaining = 1/4 → B takes 3 hrs.
Explanation by: Hriday
Work done in 3 hrs = 3(1/6+1/12)=3/4. Remaining = 1/4 → B takes 3 hrs.