Question 1024716: An airplane flies 500 mi/h in still air. Flying with the jet stream, the plane travels 1200 mi from City A to City B. The plane then returns to City A, flying against the jet stream. The round-trip flight time is 5 h. What is the speed of the jet stream in miles per hour?
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! An airplane flies 500 mi/h in still air. Flying with the jet stream, the plane travels 1200 mi from City A to City B. The plane then returns to City A, flying against the jet stream. The round-trip flight time is 5 h. What is the speed of the jet stream in miles per hour?
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With wind DATA:
dist = 1200 mi ; rate = 500+w mph ; time = 1200/(500+w) hrs
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Against wind DATA:
dist = 1200 mi ; tate = 500-w mph ; time = 1200/(500-w) hrs
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time + time = 5 hrs.
1200/(500+w) + 1200/(500-w) = 5 hrs
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1200(500-w) + 1200(500+w) = 5(500^2-w^2)
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1200000 = 5(250000) - 5w^2
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5w^2 = 50,000
w^2 = 10,000
wind = 100 mph
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Cheers,
Stan H.
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