Flying with the wind, a small plane flew 404 mi in 2 h. Flying against the wind, the plane could fly only 386 mi in the same amount of time. Find the rate of the plane in calm air and the rate of the wind.
rate of the plane: ____ mph
rate of wind: ____ mph

Respuesta :

Answer: rate of the plane is 197.5 mph

rate of wind is 4.5 mph

Step-by-step explanation:

Let x represent the rate of the plane in calm air.

Let y represent the rate of the wind.

Flying with the wind, a small plane flew 404 mi in 2 h. This means that the total speed with which the plane flew is (x + y) mph.

Distance = speed × time

Distance travelled by the plane while flying with the wind is

404 = 2(x + y)

Dividing both sides of the equation by 2, it becomes

202 = x + y- - - - - - - - - - - 1

Flying against the wind, the plane could fly only 386 mi in the same amount of time. This means that the total speed at which the plane flew is (x - y) mph.

Distance = speed × time

Distance travelled by the plane while flying against the wind is

386 = 2(x - y)

Dividing both sides of the equation by 2, it becomes

193 = x - y- - - - - - - - - - - 2

Adding equation 1 to equation 2, it becomes

395 = 2x

x = 395/2

x = 197.5

Substituting x = 197.5 into equation 1, it becomes

202 = 197.5 + y

y = 202 - 197.5

y = 4.5