Two pipes L and J can alone fill a tank in 10 hours and 12 hours respectively. Pipe P can alone empty the same tank in 60 hours. If all three pipes are opened together, then in how many hours will the tank be filled?
1
10
2
15
3
6
4
12
Two pipes L and J can alone fill a tank in 10 hours and 12 hours respectively. Pipe P can alone empty the same tank in 60 hours. If all three pipes are opened together, then in how many hours will the tank be filled?