defence exam SSB Head Constable (Communication) 2023 Mock Test Quantitative Aptitude Time and Work Pipe and Cistern
Tap P can fill a cistern in 6 hours and tap Q can empty the full cistern in 10 hours. If both taps P and Q are kept open simultaneously, then in how many hours will the empty cistern be completely full ?
1
15
2
18
3
12
4
None of the above