Solve the problem.
-An airplane flies 480 miles with the wind and 320 against the wind in the same length of time. If the speedof the wind is 30, what is the speed of the airplane in still air?
A)150 mph
B)140 mph
C)155 mph
D)60 mph

Question

Quizplus · Accepted Answer

The speed of the airplane in still air can be found by setting up the equation for time, where time = distance/speed. Let the speed of the airplane in still air be x mph. With the wind, the speed is (x + 30) mph, and against the wind, the speed is (x - 30) mph. Since the times are equal, we have 480/(x + 30) = 320/(x - 30). Solving for x gives x = 150 mph.

Solve the Problem. -An Airplane Flies 480 Miles with the Wind and 320