Answer: 20mi/hr
When an object flying with a tailwind, the speed of wind will increase the object velocity. When an object flying against the wind, the speed of wind will decrease the object velocity. Let say the speed of the wind is v. Then, the equation would be:
x + v= 485mi/hr
x - v =445mi/hr
______________-
x+ v - (x-v) = 485-445
2v= 40
v=20