<PRE><B>Question 489777</B>
Joshua can finish a certain job in 4 days while Kevin can finish the same job in 2 days. How long will it take them to finish the job it they work together?
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Joshua rate = 1/4 job/day
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Kevin rate =  1/2 job/day
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Together rate = 1/x job/day
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Equation:
rate + rate = together rate
1/4 + 1/2 = 1/x
x + 2x = 4
3x = 4
x = 4/3 days = 1 1/3 days (time for them to do the job together)
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Cheers,
Stan H.
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