SOLUTION: The amount of time it takes p people to paint d doors varies directly with the number of doors and inversely with the number of people. Four people can paint 10 doors in 2 hours. H

Question 979862: The amount of time it takes p people to paint d doors varies directly with the number of doors and inversely with the number of people. Four people can paint 10 doors in 2 hours. How many people will it take to paint 25 doors in 5 hours?
Answer by rothauserc(4718) (Show Source): You can put this solution on YOUR website!
time = k * ( d / p ) where k is the constant of proportionality
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2 = k * (10/4)
10k = 8
k = 8/10 = 4/5
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5 = (4/5) * (25/p)
5 = 100 / 5p
25p = 100
p = 4
therefore
4 people will paint 25 doors in 5 hours

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