Question

6.
a
Two pipes can fill a tank in 10 hours and 12 hours
respectively while a third pipe empties the full
tank in 20 hours. If all the three pipes are opened
simultaneously, in how much time the tank will
be filled ?
(a) 7 hours
(b) 8 hours
(c) 7 hours 30 minutes (d) 8 hours 30 minutes​

Answer 1

Answer:

Option C is the correct one...