Question 1031218
 Sue can collect data from 5 more houses per hour than Joe.
Joe rate = x houses/hour
Sue rate = (x+5) houses/hour
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 It took Sue 2 hours less to collect data from 120 houses than it took Joe to collect data from the same number of houses. What is Joe's rate of collecting data.
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Sue time to collect 120 houses:: 120/(x+5)) 
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Joe time to collect 120 houses 120/x) = 120x
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120/x - 120/(x+5) = 2 hrs
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120(x+5) - 120x = 2x(x+5)
600 = 2x^2 + 10x
x^2 + 5x - 300 = 0
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x = 15 houses per hour (Joe's rate)
x+5 = 20 houses per hour (Sue's rate)
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Cheers,
Stan H.