SOLUTION: susie can rake all of the leaves on her lawn in 12 hours. lori takes 18hours to do the same job. how long does it take for them to rack the lawn together

Question 712686: susie can rake all of the leaves on her lawn in 12 hours. lori takes 18hours to do the same job. how long does it take for them to rack the lawn together

Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
susie can rake all of the leaves on her lawn in 12 hours. lori takes 18hours to do the same job. how long does it take for them to rack the lawn together
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Susie rate: 1/12 job/hr
Lori rate:: 1/18 job/hr
Together rate: 1/x job/hr
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Equation:
rate + rate = together rate
1/12 + 1/18 = 1/x
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Multiply thru by 36x to get:
3x + 2x = 36
5x = 36
x = 7 1/5 hrs (time to do the job together)
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Cheers,
Stan H.
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