An aircraft can fly 960 miles in 4 hours with the wind and t

An aircraft can fly 960 miles in 4 hours with the wind and travel the same distance against the wind in 6 hours. What is the wind speed?

Solution

let \"p\" be the speed of the plane in calm air
Let \"w\" be the wind speed
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With the wind DATA:
distance = 960 miles ; time = 4 hrs ; rate = 960/4= 240 mph
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Against the wind DATA:
distance = 960 miles ; time = 6 hrs ; rate = 960/6 = 160 mph
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Eqations:
p + w = 240 mph
p - w = 160 mph
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2p = 400 mph
p = 200 mph (speed of the plane in calm air)
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200 + w = 240
w = 40 mph (wind speed)