Question 607369
Flying with the wind, a plane flew 800 mi in 4 h. Against the wind, the plane required 8 h to fly the same distance. Find the rate of the plane in calm air and the rate of the wind
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Find the groundspeeds upwind and downwind.
The plane's airspeed (called the rate of the plane in calm air by amateurs and writers of math books) is the average of the 2.
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The windspeed is the difference between the groundspeed and the airspeed.