SOLUTION: jim ran 12 miles in 45 minutes less than it took jon to walk 5 miles. if jim's speed was 5 miles faster than jon's speed, what was jim's speed.
i need help ASAP, please and than
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-> SOLUTION: jim ran 12 miles in 45 minutes less than it took jon to walk 5 miles. if jim's speed was 5 miles faster than jon's speed, what was jim's speed.
i need help ASAP, please and than
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Question 182645: jim ran 12 miles in 45 minutes less than it took jon to walk 5 miles. if jim's speed was 5 miles faster than jon's speed, what was jim's speed.
i need help ASAP, please and thank you!! Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! jim ran 12 miles in 45 minutes less than it took jon to walk 5 miles. if jim's speed was 5 miles faster than jon's speed, what was jim's speed.
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Jon DATA:
time = x hrs; distance = 5 miles ; rate = d/t = 5/x mph
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Jim DATA:
distance = 12 miles ; time = x-(3/4) hr; rate = d/t = 12/(x-(3/4))
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Equation:
jim rate = jon rate + 5
12/(x-(3/4)) = (5/x) + 5
48/(4x-3) = (5 + 5x)/x
48x = 5(x+1)(4x-3)
48x = 5[4x^2 +x - 3]
20x^2 - 43x - 15 = 0
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x = [43 +- sqrt(43^2 - 4*20*-15)]/40
x = [43 + 55.22]/40
x = 2.455 mph
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Jim's rate = d/t = 12/(x-(3/4))
Jim's rate = 12/(2.455-0.75) = 7.038 mph
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Cheers,
Stan H.
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