A plane can fly 1200 miles with the wind in 3 hours while it

A plane can fly 1200 miles with the wind in 3 hours, while it takes the same plane 4 hours to fly the same distance against the wind. Find the speed of the plane in still air and the speed of the wind.

Solution

1200 miles in 3 hr --> 400 mph
1200 miles in 4 hr --> 300 mph
The airspeed is the average, 350 mph.
The windspeed is the difference, 50 mph.
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The \"speed in still air\" is called airspeed.
The 400 mph downwind and the 300 mph upwind are called ground speed.