<PRE><B>Question 79608</B>
1 pipe will fill a container in 20 minutes, the second pipe will fill the container in 30 minutes, how long will it take to fill the conatiner with both pipes?
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First pipe DATA:
Time = 20 min/job : Rate = 1/20 job/min
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Second pipe DATA:
Time = 30 min/job ; Rate = 1/30 job/min
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Together DATA:
Time = x min/job ; Rate = 1/x job/min
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EQUATION:
1st pipe rate + 2nd pipe rate = together rate
1/20 + 1/30 = 1/x
Multiply thru by 60x to get:
3x + 2x = 60
5x = 60
x= 12 min/job (time required for pipes working together to do the job)
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Cheers,
Stan H.
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