Question 254718
This is an RTD problem, Here is the table based on given information.
wind . . . . . . .rate . . . . . . . .time . . . . . . . .distance
against . . . . . r - c . . . . . . . .5 . . . . . . .. .  .. 400
with . . . . . . . .r + c . . . . . . . 2 . . . . . . .. . . . 400
--
r-c = 80
r+c = 200
adding down we get
2r = 280
r = 140.