Question 469852: Fred can paint a house in 10 hours. Together, Pat and Fred can paint the house in 8 hours. Which equation, when solved, will produce the number of hours needed for Pat to paint the house alone?
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! Fred can paint a house in 10 hours. Together, Pat and Fred can paint the house in 8 hours. Which equation, when solved, will produce the number of hours needed for Pat to paint the house alone?
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Fred time = 10 hr/job ; rate = 1/10 job/hr.
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Together time = 8 hrs/job ; rate = 1/8 job/hr
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Pat time = x hr/job ; rate = 1/x job/hr
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Equation:
rate + rate = together rate
1/10 + 1/x = 1/8
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or you might use
8x + 80 = 10x
2x = 80
x = 40 hrs (time for Pat to do the job alone)
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Cheers,
Stan H.
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