Three taps A, B, C can fill an overhead tank in 4, 6 and 12 hours respectively. How long would the three taps take to fill the tank if all of them are opened together ?

Explanation

1 Time taken by tap A to fill the tank in one hour = 4 1 Time taken by tap B to fill the tank in one hour = 6 1 Time taken by tap C to fill the tank in one hour = 12 1 1 1 6 1 Time taken by all taps to fill the tank in one hour = 4 + 6 + 12 or 12 or 2 Total time taken by all three taps together to fill the tank = 2 hours. Hence, option A is the correct answer.