Question 280263: A water tank has an inlet pipe and a drain pipe, a full tank can be emptied in 30 min. if the drain is opened and an empty tank can be filled in 45 min. with the inlet pipe opened,if both pipes are accidentally opened when the tank is full,how longwill it take to empty the tank?
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! A water tank has an inlet pipe and a drain pipe, a full tank can be emptied in 30 min. if the drain is opened and an empty tank can be filled in 45 min. with the inlet pipe opened,if both pipes are accidentally opened when the tank is full,how longwill it take to empty the tank?
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Emptying time = 1/2 hr/job ; Emptying Rate = 2 job/hr
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Filling time = 3/4 hr/job ; Filling Rate = 4/3 job/hr
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Together Rate: 1/x job/hr
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Equation:
rate - rate = 1/x
2 - 4/3 = 1/x
2/3 = 1/x
x = 3/2 or 1hr 30min to empty the tank
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Cheers,
Stan H.
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