Tap A can fill a tank in 6 hours, tap B can fill the same tank in 8 hours and tap C can empty the same tank in 4 hours. If all three taps A, B and C are opened together, then how much time (in hours) will be taken to fill the tank?

Answer: Option A

Solution

Answer: Option A

Solution:

Total work in a hours by (A + B + C) = 4 + 3 - 6 = 1
A + B + C = $$\frac{24}{1}$$ = 24 hours