Three taps A, B and C can fill thetank in 40, 48 and 60 hours respectively.

Explanation

⇒ Tap A can fill in 40 hours ⇒ Tap A’s 1 hour work = 1 / 40 ----1 ⇒ Tap B can fill in 48 hours ⇒ Tap B’s 1 hour work = 1 / 48 ----2 ⇒ Tap C can fill in 60 hours ⇒ Tap C’s 1 hour work = 1 / 60 ----3 ⇒ Now Tap A, B and C’s 1 hours work = 1/40 + 1/48 + 1/60 ⇒ Tap A, B and C’s 1 hours work = (6 + 5 + 4)/240 ⇒ Tap A, B and C’s 1 hours’ work = 1/16 ∴ A, B and C can fill the tank together in 16 hours