Pipes A and B can fill a tank in 5 hours and 6 hours, respectively. Pipe C can empty it in 12 hours. If all three pipes are opened together, the tank will be filled in:
A
6 9/17
B
3 9/17
C
5 9/17
D
4 9/17
Correct Option:
B
Explanation
Net rate = 1/5+1/6-1/12 = (12+10-5)/60 = 17/60.
Time = 60/17 = 3 9/17 hours.
