<PRE><B>Question 844029</B>
6 men take 3 days to dig 8 ditches
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1/3 as many men would take 3 times longer
to dig the same number of ditches, so
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2 men take 9 days to dig 8 ditches
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twice as many men take half as long
to dig the same number of ditches, so
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4 men take 9/2 days to dig 8 ditches
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The same number of men take 1/4 of that 
time to build 1/4 as many ditches, so
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4 men take 9/8 days to build 2 bridges
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It takes 5 times as long for the same number
of men to dig 5 times as many bridges, so
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4 men take 45/8 days to build 10 bridges
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{{{ 45/8 =  5 + 5/8 }}}
4 men take 5 and 5/8 days to build 10 bridges

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