<PRE><B>Question 880096</B>
It takes 3 wks to make 15 birdhouses
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In 1/3 of that time, you could only
make 1/3 as many, so
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In 1 wk you can make 5 birdhouses
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It will only take 1/5 of that time to make 
1 birdhouse, so
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In 1/5 of a wk, you can make 1 birdhouse
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11 birdhouses will take 11 times as long, so
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it takes 11/5 = 2 1/5 weeks to build 11 birdhouses

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