<PRE><B>Question 677610</B>
The hot water faucet takes 4 minutes to fill the tub, and the cold water faucet takes 3 minutes. How long will it take to fill the tub if both are used?
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hot water rate: 1/4 job/min
cold water rate: 1/3 job/min
together rate: 1/x job/min
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Equation:
1/4 + 1/3 = 1/x
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3x + 4x = 12
7x = 12
x = 12/7 hr = 1 min 42 sec(time to do the job together)
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Cheers,
Stan H.</PRE>