SOLUTION: Bill can mow his mother's lawn in 6 minutes. His brother Jim can mow it in 9 minutes. How long will it take them to do it together, if each has his own lawnmower?

Question 1006585: Bill can mow his mother's lawn in 6 minutes. His brother Jim can mow it in 9 minutes. How long will it take them to do it together, if each has his own lawnmower?
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
Bill can mow his mother's lawn in 6 minutes. His brother Jim can mow it in 9 minutes. How long will it take them to do it together, if each has his own lawnmower?
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Bill's rate = 1/6 job/min
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Jim's rate = 1/9 job/min
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Together rate:: 1/x job/min
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Equation:
1/6 + 1/9 = 1/x
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9x + 6x = 6*9
15x = 6*9
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x = 3.6 min or 3min 36sec (time to do the job together)
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Cheers,
Stan H.
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