Question : Three pipes A, B, and C can fill a tank in 6 hours, 9 hours, and 12 hours, respectively. B and C are opened for half an hour, and then pipe A is opened. The time taken by the three pipes together to fill the remaining part of the tank is:
Option 1:
Option 2:
Option 3:
Option 4:
Correct Answer:
Solution :
Given:
Three pipes A, B, and C can fill a tank in 6 hours, 9 hours, and 12 hours respectively.
So, L.C.M of 6, 9, 12 = Total capacity = 36 units
Efficiency of A =
Efficiency of B =
Efficiency of C =
In half an hour (B + C) must have filled
Capacity left
Now all pipes will fill the remaining tank in
Hence, the correct answer is