Question 643781: suppose a garden can be raked by one gardener in 7 hours and by a second in 5 hours. how long would it take if they worked together? Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! suppose a garden can be raked by one gardener in 7 hours and by a second in 5 hours. how long would it take if they worked together?
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1st gardener rate: 1/7 job/hr
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2nd gardener rate: 1/5 job/hr
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Together rate: 1/x job/hr
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Equation:
rate + rate = together rate
1/7 + 1/5 = 1/x
5x + 7x = 35
12x = 35
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x = 35/12 = 2 11/12 hrs = 2 hr 55 min (time to do the job together)
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Cheers,
Stan H.
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