460 / 2.5 =184mph travelling against the wind
460 / 2 =230mph travelling with the wind
230 - 184=46 / 2 =23mph rate of the wind
[230+184] / 2 =207mph rate of the plane without wind.
So, the answer is:
The airplane flies at 207 mi/h with no wind. The rate of the wind is 23 mi/h.