Question

When a plane flies with the wind, it can travel 920 miles in 2 hours. When the plane flies in the opposite direction against the wind it takes 4 hours to fly the same distance. Find the rate of the plane in still air and the rate of the wind.

Answer 1

w = wind

r = plane with no wind (in still air)

r + w = 920/2

r - w = 920/4

r + w = 460 (1)

r - w = 230 (2)

Add equation (1) & (2)

2r = 690

r= 345

the rate of the plane in still air 345 mph

Now we replace the value of r in eq 1.

345 + w = 460

w = 460 - 345

w= 115 mph (rate of the wind)