Question 1014664
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Rate going=450 mi/3 hours= 150 mi/hr
Rate returning=450 mi/5 hours= 90 mi/hr
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R=rate in still air; W=wind speed
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Rate going =R+W=150mph
Rate back = R-W=90 mph  Subtract this from equation above.
2W=60 mph
W=30 mph
ANSWER 1: Wind speed was 30 mph 
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R+W=150 mph
R=150mph-W
R=150mph-30mph=120mph
ANSWER 2: The speed of the plane in still air is 120 mph.
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CHECK:
R-W=90 mph
120mph-30mph=90mph
90mph=90mph
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