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put this solution on YOUR website!A certain tank can be filled by pipe A in 12 minutes. Pipe B can empty the tank in 18 minutes.
If both pipes are open, how long will it take to fill or empty the tank?
:
It takes less time to fill it than to empty it, therefore with both valves open the tank will be filled eventually
:
Let t = time to fill the tank with both valves open
Let a full tank = 1
-
= 1
multiply by 36
36*
- 36*
= 36(1)
Cancel the denominators, results
3t - 2t = 36
t = 36 hrs to fill the tank with both valves left open
