SOLUTION: An express train travels 150 km in the same time that a freight train travels 100km. The average speed of the freight train is 20km/h less than that of the express train. Find the

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Question 181897: An express train travels 150 km in the same time that a freight train travels 100km. The average speed of the freight train is 20km/h less than that of the express train. Find the speed of each train.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
An express train travels 150 km in the same time that a freight train travels 100km. The average speed of the freight train is 20km/h less than that of the express train. Find the speed of each train.
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Express DATA:
distance = 150 km ; rate = x km/h ; time = d/r = 150/x hrs.
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Freight DATA:
distance = 100 km; rate = (x-20) km/h ; time = d/r = 100/(x-20) hrs.
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Equation:
time = time
150/x = 100/(x-20)
100x = 150(x-20)
100x = 150x - 3000
-50x = -3000
x = 60 km/h (speed of the express train)
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x-20 = 40 km/h (speed of the freight train)
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Cheers,
Stan H.