Question

A pipe can fill a cistern is 5 hours. the cistern can be emptied by on outlet pipe in 6 hours .How much time will it take to fill the cistern if both the pipes are opened together?​

Answer 1

Answer:

Pipe (1) in Ihr = I/5

Pipe (2) in 1hr =-1/6

1/5-1/6=6/30-5/30 = 1/30

30 hrs. Ans