<PRE><B>Question 881993</B>
20 men take 30 days to do 1 job
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3 times as many men can do the job
in 1/3 of that time, so
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60 men take 10 days to do 1 job
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1/5 as many men take 5 times longer
to do 1 job, so
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12 men take 50 days to do 1 job

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