SOLUTION: Hello, can you help me solve this problem? Please?
Allan and Andrew can paint a room in 3hrs. It takes Allan 7 hrs to do this alone. Without Allan, how long will it take Andrew
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-> SOLUTION: Hello, can you help me solve this problem? Please?
Allan and Andrew can paint a room in 3hrs. It takes Allan 7 hrs to do this alone. Without Allan, how long will it take Andrew
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Question 1098169: Hello, can you help me solve this problem? Please?
Allan and Andrew can paint a room in 3hrs. It takes Allan 7 hrs to do this alone. Without Allan, how long will it take Andrew to paint the same room?
Thank you Found 2 solutions by josgarithmetic, ikleyn:Answer by josgarithmetic(39617) (Show Source):
Their combined rate of work is of the job per hour.
Allan's individual rate of work is of the job per hour.
Hence, Andrew's individual rate of work is the difference - of the job per hour.
- = - = .
Thus Andrew's individual rate of work is of the job per hour.
Hence, it will take hours = 5 hours and 15 minutes for Andrew to complete the entire job working alone.
Solved.
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It is a typical joint work problem.
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