SOLUTION: If Sally can paint a house in 4 hours and John can pain the same house in 6 hour, how long will it take for both of them to paint the house together?
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Question 152129: If Sally can paint a house in 4 hours and John can pain the same house in 6 hour, how long will it take for both of them to paint the house together? Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! If Sally can paint a house in 4 hours and John can pain the same house in 6 hour, how long will it take for both of them to paint the house together?
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Let t = time required when they work together
;
Let the completed job = 1
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We want to find out what fraction of the job each will do, has to add up to 1 + = 1
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Multiply equation by 12 to get rid of the denominators
12* + 12* = 12(1)
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Cancel the denominators and you have;
3t + 2t = 12
;
5t = 12
t =
t = 2.4 hrs working together
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Check solution on a calc: enter (2.4/4) + (2.4/6) = 1