Three taps D, E and F can fill a tank in 100, 120 and 150 minutes respectively. If all the taps are opened together, then in how many minutes will the tank be filled?

Three taps D, E and F can fill a tank in 100, 120 and 150 minutes resp

1.	Three taps D, E and F can fill a tank in 100, 120 and 150 minutes respectively. If all the taps are opened together, then in how many minutes will the tank be filled?
A.	50
B.	60
C.	40
D.	70
Answer» D. 70