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Monday, July 6, 2009
Paint Job
One painter could paint the house in 14 days. When working together with his son, he could paint the house in 10 days. How many days would it take to paint the house, if the painter's son works alone?
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3 comments:
Let x=son alone
(1/14) + (1/x) = (1/10)
(140/x) = 4
(140/4) = x
35 = x
It would take the son 35 days to complete the task alone.
18
Kalonni is absolutely right.
Father's speed of painting is 1/14th of the house per day. Son's speed is 1/x with x being number of days son could paint the house alone. Together, their speed is 1/10th of the house per day.
You are steadily moving up the winners' list!
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