<PRE><B>Question 730702</B>
 If 12 men working 8hrs a day can do a piece of work in 15 days, how many hrs a day must 20 men work in order to do it in 8 day?
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hrs is indirectly related to # of days and to # of men
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h = k/(d*m)
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Solve for &quot;k&quot; using 
&quot;12 men working 8hrs a day can do a piece of work in 15 days&quot;
8 = k/(15*12)
k = 1440
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Equation:
h = 1440/(d*m)
how many hrs a day must 20 men work in order to do it in 8 day?

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h = 1440/(8*20)
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hrs per day = 9
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Cheers,
Stan H.
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