SOLUTION: Jack usually mows his lawn in 5 hours. Mary can mow the same yard in 3 hours. how much time would it take for them to mow the lawn together? they could mow the lawn in ????
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-> SOLUTION: Jack usually mows his lawn in 5 hours. Mary can mow the same yard in 3 hours. how much time would it take for them to mow the lawn together? they could mow the lawn in ????
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Question 346078: Jack usually mows his lawn in 5 hours. Mary can mow the same yard in 3 hours. how much time would it take for them to mow the lawn together? they could mow the lawn in ???? Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! Jack usually mows his lawn in 5 hours. Mary can mow the same yard in 3 hours. how much time would it take for them to mow the lawn together? they could mow the lawn in ????
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Jack rate: 1/5 job/hr
Mary rate: 1/3 job/hr
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Together rate: 1/x job/hr
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Equation:
rate + rate = together rate
1/5 + 1/3 = 1/x
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3x + 5x = 15
8x = 15
x = 15/8 = 1 7/8 hr
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1 7/8 hr = 1hr (7/8)60 min = 1hr 52.5 minutes (time together)
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Cheers,
Stan H.
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