<PRE><B>Question 806193</B>
10 men do 1 wall in {{{ 3*8 = 24 }}} hrs
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Note that {{{ 15*8 = 120 }}} hrs
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1/5 as many men will take 5 times as long 
to do 1 wall
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So, 2 men do 1 wall in {{{ 5*24 = 120 }}} hrs
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To do 3 walls in this time will take 
3 times as many men, so
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6 men can complete 3 walls in 120 hrs,
or 15 days  working 8 hrs a day

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