Question 268325: With the wind a jet can fly 2500km in 2 hours 30 min. Against the wind, it can fly only 2000km in the same time. Find the rate of the jet in still air and the rate of the wind.
Found 2 solutions by stanbon, Alan3354:
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! With the wind a jet can fly 2500km in 2 hours 30 min.
With wind DATA:
distance = 2500 km ; time = 2.5 hrs ; rate = 2500/2.5 = 100 kmh
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Against the wind, it can fly only 2000km in the same time.
Against wind DATA:
distance = 2000 km ; time = 2.5 hrs ; rate = 2000/2.5 = 800 kmh
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Find the rate of the jet in still air and the rate of the wind.
p + w = 100
p - w = 80
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2p = 180
p = 90 kmh (plane speed in still air)
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Since p+w = 100, w = 10 kmh (wind speed)
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Cheers,
Stan H.
Answer by Alan3354(69443)  (Show Source):
You can put this solution on YOUR website! With the wind a jet can fly 2500km in 2 hours 30 min.
With wind DATA:
distance = 2500 km ; time = 2.5 hrs ; rate = 2500/2.5 = 1000 kmh
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Against the wind, it can fly only 2000km in the same time.
Against wind DATA:
distance = 2000 km ; time = 2.5 hrs ; rate = 2000/2.5 = 800 kmh
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The airspeed is the average, 900 kph
The windspeed is the difference, 100 kph
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Airplanes don't use kilometers and kph, they use nautical miles and knots.
1 knot = 1 nm/hr
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Pilots don't use "speed in still air", it's airspeed.
Airspeed + k*windspeed = ground speed
(k because the wind is not always a direct headwind or tailwind)
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