Question 288500
A cyclist travels 84 mi in 7 hours going against the wind.
rate = 84/7 = 12 mph
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She travels 140 mi with the wind in the same amount of time.
rate = 140/7 = 20 mph
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What is the rate of the cyclist in still air and what is the rate of the wind?
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Equations:
c + w = 20
c - w = 12
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Add and solve for c:
2c = 32
c = 16 mph (rate of the cyclist in still air)
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Since c+w = 20 , w = 4 mph (rate of the wind)
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cheers,
Stan H.