Pipes A and B can fill a tank in 4 and 2 hours. Pipe C can empty it in 8 hours. If all pipes are opened together, then the tank will be filled in?
Choose the correct choice from the following:
A) 3/2hr	B) 1/2hr	C) 8/5hr	D) 9/7hr	E) 5/3hr
Net part filled in 1 hour = 1/4 + 1/2 - 1/8 = 5/8   The tank will be full in 8/5 hr   Answer is 8/5hr
<result>C</result>
Pipes A and B can fill a tank in 4 and 2 hours. Pipe C can empty it in 8 hours. If all pipes are opened together, then the tank will be filled in?