SOLUTION: A plane can fly 355 mph in still air. If it can fly 210 miles downwind in the same amount of time it can fly 145 miles upwind, find the velocity of the wind.

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Question 988303: A plane can fly 355 mph in still air. If it can fly 210 miles downwind in the same amount of time it can fly 145 miles upwind, find the velocity of the wind.
Answer by macston(5194) About Me  (Show Source):
You can put this solution on YOUR website!
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W=speed of wind
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210mi%2F%28355mph%2BW%29=145mi%2F%28355mph-W%29 Cross multiply.
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210mi%28355mph-W%29=145mi%28355mph%2BW%29
74550mi%5E2%2Fhr-210miW=51475mi%5E2%2Fhr%2B145miW Subtract 51475mi^2/hr from each side.
23075mi%5E2%2Fhr=355miW Divide each side by 355mi.
65mi%2Fhr=W
ANSWER: The wind speed was 65 mph.