Pipes A and B fill a tank in 5 and 6 hours respectively. Pipe C empties the tank in 12 hours, if you open all the three pipes together this tank will be filled in?  Choose the correct choice from the following options
A) 3 9/17 hours	B) 4.5 hours	C) 1.25 hours	D) 4 7/17 hours	E) None of these
Explanation:   It is given that Pipe A,B and C work simultaneously.   Pipe A and B are filling the tank and Pipe C is emptying it.   In 1 hour volume of tank filled by Pipe A: 1/5th   In 1 hour volume of tank filled by Pipe B: 1/6th   In 1 hour volume of tank emptied by Pipe C: 1/12th   Working together Pipe A B and C fill x volume of tank.   =&gt;1/x = (1/5)+(1/6)-(1/12)   =&gt;x=60/17 hours   3 9/17 hoursNSWER 3 9/17 hours
<result>A</result>
Pipes A and B fill a tank in 5 and 6 hours respectively. Pipe C empties the tank in 12 hours, if you open all the three pipes together this tank will be filled in?