Solve.
-A jet plane traveling at a constant speed goes 1200 miles with the wind, then turns around and travels for 1000 miles against the wind. If the speed of the wind is 50 mph and the total flight took 4 hours, find the speed of the
Plane in still air.
A)605 mph
B)550 mph
C)525 mph
D)435 mph

Question

Quizplus · Accepted Answer

Let the speed of the plane in still air be x mph. With the wind, the speed is (x + 50) mph, and against the wind, it is (x - 50) mph. The time taken to travel 1200 miles with the wind is 1200/(x + 50) hours, and the time taken to travel 1000 miles against the wind is 1000/(x - 50) hours. The total time is 4 hours. Therefore, 1200/(x + 50) + 1000/(x - 50) = 4. Solving this equation gives x = 550 mph.

Solve. -A Jet Plane Traveling at a Constant Speed Goes 1200