SOLUTION: joseph can paint a 300 yd2 fence in 6 hours. scott can paint the same size fence in 5 hours, and dave can paint the same side fence in 7 hours. approximately how long will it take

Algebra ->  Rate-of-work-word-problems -> SOLUTION: joseph can paint a 300 yd2 fence in 6 hours. scott can paint the same size fence in 5 hours, and dave can paint the same side fence in 7 hours. approximately how long will it take      Log On


   



Question 952600: joseph can paint a 300 yd2 fence in 6 hours.
scott can paint the same size fence in 5 hours, and dave can paint the same side fence in 7 hours. approximately how long will it take to paint the fence if they paint simultaneously

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
joseph can paint a 300 yd2 fence in 6 hours.
scott can paint the same size fence in 5 hours, and dave can paint the same side fence in 7 hours. approximately how long will it take to paint the fence if they paint simultaneously
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Joesph rate:: 1/6 job/hr
Scott rate:: 1/5 job/hr
Dave rate:: 1/7 job/hr
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Together rate: 1/x job/hr
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Equation:
rate + rate + rate = together rate
1/6 + 1/5 + 1/7 = 1/x
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35x + 42x + 30x = 6*5*7
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107x = 210
x = 1.96 hrs = 1 hr 57 min 36 seconds (time to do the job together)
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Cheers,
Stan H.
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