Answer:the speed of the wind is 20 miles per hour.
Step-by-step explanation:
A Plane flies at x miles per hour in still air. This means that the normal speed of the plane is x miles per hour.
Let y represent the speed of the wind.
Flying with a tailwind, it's speed is 485 miles per hour. This means that
the total speed of the plane would be x + y. Therefore
x + y = 485 - - - - - - - - 1
Against the wind, it's air speed is only 445 miles per hour. This means that
the total speed of the plane would be x - y. Therefore
x - y = 445 - - - - - - - - - 2
Adding equation 1 and equation 2, it becomes
2x = 930
x = 930/2 = 465
Substituting x = 465 into equation 1, it becomes
465 + y = 485
y = 485 - 465
y = 20 miles per hour