Pipe A can fill a tank in 10 hours, pipe B in 5 hours and pipe C in 5 hours. If all the pipes are open, in how many hours will the tank be filled?	Select
A) 2 hours B) 3 hours C) 4 hours D) 5 hours E) 6 hours
Part filled by A + B + C in 1 hour = 1/10 + 1/5 + 1/5= 1/2   All the three pipes together will fill the tank in 2 hours.   2 hoursnswer:2 hours
<result>A</result>
Pipe A can fill a tank in 10 hours, pipe B in 5 hours and pipe C in 5 hours. If all the pipes are open, in how many hours will the tank be filled?