SOLUTION: If Sally can paint a house in 4 hours, and John can paint 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 80456: If Sally can paint a house in 4 hours, and John can paint the same house in 6 hour, how long will it take for both of them to paint the house together?
You can put this solution on YOUR website! If Sally can paint a house in 4 hours, and John can paint 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 to complete the job together
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Let the completed job = 1
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A simple equation: + = 1
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Multiply equation by 12 to get rid of the denominators, you then have:
3t + 2t = 12
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5t = 12
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t = 12/5
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t = 2.4 hrs working together
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Check solution of t = 2.4:
2.4/4 + 2.4/6 =
.6 + .4 = 1