<PRE><B>Question 719994</B>
Will can paint six rooms in 12 hours working alone If his friend Matthew helps him together they can paint the six rooms in 7 hours How long would it take Matthew to paint the 6 rooms by himself?
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Will rate: 1/12 job/hr
Together rate: 1/7 job/hr
Matt rate = 1/x job/hr
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Equation:
rate + rate = together rate
1/12 + 1/x = 1/7
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7x + 84 = 12x
5x = 84
x = 16.8 hrs = 16 hr 48 minutes (time for Matt to do the job alone)
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Cheers,
Stan H.
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