<PRE><B>Question 811313</B>
5 men can complete a job in 4 days
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Twice as many men can do the same 
job in half the time, so
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10 men can do the job in 2 days
working at the same rate
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Working at 1/4 of that rate, the
10 men take 4 times as long, so
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10 men do the job in 8 days
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