Question

If a plane can travel 480 miles per hour with the wind and 400 miles per hour against the​ wind, find the speed of the wind and the speed of the plane in still air.

Answer 1

Let "p" be speed of plane in still air.

Let "c" be speed of the wind.

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Equations:

p + c = 480 mph

p - c = 400 mph

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Add and solve for "p":

2P = 880

p = 440 mph (speed of the plane in still air)