SOLUTION: When a plane flies with the​ wind, it can travel 840 miles in 2 hours. When the plane flies in the opposite​ direction, against the​ wind, it takes 5 hours to fly the same di

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: When a plane flies with the​ wind, it can travel 840 miles in 2 hours. When the plane flies in the opposite​ direction, against the​ wind, it takes 5 hours to fly the same di      Log On


   

Question 1158750: When a plane flies with the​ wind, it can travel 840 miles in 2 hours. When the plane flies in the opposite​ direction, against the​ wind, it takes 5 hours to fly the same distance. Find the rate of the plane in still air and the rate of the wind.
Answer by VFBundy(438) About Me  (Show Source):
You can put this solution on YOUR website!
With the wind:
Distance = 840
Rate = d/t = 420
Time = 2

Against the wind:
Distance = 840
Rate = d/t = 168
Time = 5

Let s = rate in still air
Let w = speed of wind

s + w = 420
s - w = 168

2s = 588

s = 294

If s = 294, and s + w = 420, then w = 126

s = rate in still air = 294
w = speed of wind = 126