SOLUTION: Fred can mow the lawn in 1 hour. John can mow the lawn in 2 hours. How long will it take them to mow the lawn together?

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Question 396338: Fred can mow the lawn in 1 hour. John can mow the lawn in 2 hours. How long will it take them to mow the lawn together?
Answer by stanbon(75887)   (Show Source): You can put this solution on YOUR website!
Fred can mow the lawn in 1 hour. John can mow the lawn in 2 hours. How long will it take them to mow the lawn together?
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Fred rate = 1 job/hr
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John rate = 1/2 job/hr
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Together rate = 1/x job/hr
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Equation:
rate + rate = together rate
1 + 1/2 = 1/x
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Multiply by 2x to get:
2x + x = 2
3x = 2
x = 2/3 hr (time to do the job together)
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Cheers,
Stan H.
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