Question

Two pipes can fill a tank in 10 hrs and 12 hrs respectively. While a third pipe empties the full tank in 20 hrs. If all the three pipes operate together, in how much time the tank will be filled?

Answer 1

HEYA>>>>
_______________________________________The time taken when two inlets work to fill a tank is 1/10+1/12
=(12+10)/120
=22/120
=11/60
Time taken to fill the tank when two inlets and one outlet is present
=11/60-1/20
=(11-3)/60
=8/60
=2/15 hrs

......................................................................................................Hope it helps