<PRE><B>Question 909157</B>
12 painters paint 4 rooms in 6 days
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It will take 3 times as many painters to
paint 3 times as many rooms in the same time
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36 painters paint 12 rooms in 6 days
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In 1/2 that time, it will take twice as many 
painters to paint the same number of rooms
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72 painters paint 12 rooms in 3 days
( you meant 3 days, not 3 hours, right? )
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