Taps A and B can fill a tank in 15 minutes and 10 minutes respectively while tap C can empty the full tank in X minutes. If all the three taps are opened together, the tank is filled completely in 8 minutes. Tap C alone will empty (3/8)th part of the tank in:
Show answer & explanation
Correct answer: A
Explanation
The correct answer is Option 1 i.e. 9 minutes
| Concept | Application |
| If a pipe can fill a tank in p minutes, then: part filled in 1minute = (1/p) |
If all the three taps are opened together, the tank is filled completely in 8 minutes. 8{(1/15 + 1/10) - (1/x)} = 1 ⇒{(1/6) - (1/x)} = (1/8) ⇒ (1/x) = (1/6) - (1/8) = (1/24) ⇒ x = 24 C alone can empty the tank in 24 minutes. Tap C alone will empty (3/8)th part of the tank in = 24 × (3/8) = 9 minutes |