<PRE><B>Question 151070</B>
A worker can cover a parking lot with asphalt in ten hours. With the help of an assistant, they can do the job in six hours.  How long would it take the assistant working alone to cover the parking lot with asphalt?
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Worker DATA:
time = 10 hrs/job ; rate = (1/10) job/hr
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Together  DATA:
time = 6 hrs/job ; rate = (1/6) job/hr
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Assistant DATA:
Time = x hrs/job ; rate = 1/x job/hr
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EQUATION:
1/10 + (1/x) = 1/6
3x + 30 = 5x
2x = 30
x = 15 hrs. (time for the assistant to do the job alone)
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Cheers,
Stan H.</PRE>