SOLUTION: An inlet pipe can fill a tank in 10 minutes.. A drain can empty the tank in 12 minutes. If the tank is empty and both the pipe and the drain are open, how long will it take before
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-> SOLUTION: An inlet pipe can fill a tank in 10 minutes.. A drain can empty the tank in 12 minutes. If the tank is empty and both the pipe and the drain are open, how long will it take before
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Question 270702: An inlet pipe can fill a tank in 10 minutes.. A drain can empty the tank in 12 minutes. If the tank is empty and both the pipe and the drain are open, how long will it take before the tank overflows?
You can put this solution on YOUR website! An inlet pipe can fill a tank in 10 minutes.. A drain can empty the tank in 12 minutes. If the tank is empty and both the pipe and the drain are open, how long will it take before the tank overflows?
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Inlet rate: 1/10 job/min
Outlet rate: 1/12 job/min
Together rate: 1/x job/min
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Equation:
inrate - outrate = together rate
1/10 - 1/12 = 1/x
2/(120) = 1/x
Invert:
x = 60 minutes
Time to fill the tank
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Cheer,
Stan H.
You can put this solution on YOUR website! Let x=time it takes for tank to overflow when both pipes are open and the tank is empty
When both pipes are open the tank fills at the rate of 1/x tank per min
Inlet pipe fills at the rate of 1/10 tank per min
drain empties at the rate of 1/12 tank per min
So, our equation to solve is:
1/10 - 1/12=1/x multiply each term by 60x
6x-5x=60
x=60 min--------------time it takes for tank to overflow when both pipes are open and the tank is empty
CK
in 60 min inlet pipe fills (1/10)*60 or 6 tanks
in 60 min drain lets out (1/12)*60 or 5 tanks
So in 60 min we have a net gain of 1 tank---any more water and it overflows
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