Question

If two taps A and B can fill a tank in 8 minutes and 48 minutes and a tap C can empty the tank in 12 minutes. Find the time taken to fill the tank completely if all the taps are opened together?
1. 15 minutes
2. 18 minutes
3. 20 minutes
4. 16 minutes

Answer 1

Correct Answer - Option 4 : 16 minutes

GIVEN:

Two taps A and B can fill a tank in 8 minutes and 48 minutes and a tap C can empty the tank in 12 minutes.

FORMULA USED:

Efficiency = Work/Time

CALCULATION:

Suppose total capacity of tank = 48 units (LCM of 8, 48 and 12)

So,

Efficiency of tap A = 48/8 = 6

Efficiency of tap B = 48/48 = 1

Efficiency of tap C = 48/12 = 4

So,

Required time = 48/(6 + 1 - 4) = 16 minutes