A pipe can fill an empty tank in 5 minutes, and another pipe can empty it in 6 minutes. If both the pipes are opened simultaneously, then in how much time will the tank be filled?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is Option 2 i.e. 30 min.
L.C.M of (5 and 6) = 30
The efficiency of Pipe A = 30/5 = 6 units
The efficiency of Pipe B = 30/6 = -5 units
So, time taken to fill the tank = 30/(6 - 5) = 30/1 = 30 minutes