A plane can fly 540 miles with the wind in one hour less tha

A plane can fly 540 miles with the wind in one hour less than it can fly 480 miles
against the wind. The average wind speed is 30 miles per hour. Find the speed of the plane in still air.

Solution

It\'s 540 - 30 = 510 mph
or 480 + 30 = 510 mph
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The \"speed of the plane in still air\" is called the airspeed. The people writing textbooks don\'t know much.
Also, planes use knots for speed, and wind speed is in knots, not miles per hour.