SOLUTION: Together, Stanley and Elsie can mow a lawn in 3 hours. It takes elsie 5 hours to mow the lawn alone. How long would it take Stanley working by himself?

Question 602759: Together, Stanley and Elsie can mow a lawn in 3 hours. It takes elsie 5 hours to mow the lawn alone. How long would it take Stanley working by himself?
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
Together, Stanley and Elsie can mow a lawn in 3 hours. It takes elsie 5 hours to mow the lawn alone. How long would it take Stanley working by himself?
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Together rate: 1/3 job/hr
Elsie rate: 1/5 job/hr
Stan rate: 1/x job/hr
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Equation:
rate + rate = together rate
1/5 + 1/x = 1/3
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Multiply thru by 15x to get:
3x + 15 = 5x
2x = 15
x = 7.5 hrs. (Stan's time to do the job alone)
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Cheers,
Stan H.
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