Question 815066: If it takes 3 people 4 hours to plant 12 trees, how many trees can 5 people plant in 5 hours? Found 2 solutions by josmiceli, vindeep:Answer by josmiceli(19441) (Show Source):
You can put this solution on YOUR website! It takes 3 people 4 hours to plant 12 trees
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If the same number of people plant for 1/4
of that time, they will plant 1/4 as many trees, so
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3 people take 1 hour to plant 3 trees
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1/3 as many people will plant 1/3 as many trees
in the same amount of time, so
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1 person takes 1 hour to plant 1 tree
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5 times as many people will plant 5 times as
many trees in the same amount of time, so
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5 people take 1 hour to plant 5 trees
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The same number of people take 5 times as long
to plant 5 times as many trees, so
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5 people take 5 hours to plant 25 trees
You can put this solution on YOUR website! 3P : 4Hr : 12 T = 5 P : 5 Hr : xT
case 1: rate /person = 12 / ( 3 X 4 )
case 2 : rate / person = x / ( 5 X 5 )
solving for x gives , x = 25 Trees
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