<PRE><B>Question 916524</B>
Julia and Robert can finish a piece of work in 15 days. Julia can do the job alone in 20 days. How long would it take Robert to do the task alone?
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together rate = 1/15 job/day
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Julia rate = 1/20 job/day
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Robert rate = 1/x job/day
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Equation:
rate + rate = together rate
1/x + 1/20 = 1/15
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1/x = 1/15 - 1/20
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1/x = (20-15)/(15*20) = 5/(15/20) = 1/60
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x = 60 days (time for Robert to do the job alone)
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Cheers,
Stan H.
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