Answer: speed of plane in still air is 180 miles per hour
speed of the wind is 18 miles per hour
Step-by-step explanation:
Flying with the wind, the plane went 198 miles per hour. This means if was flying in the same direction with the wind. This is same as the speed in still air because there was no opposition from the wind.
Flying into the same wind the plane only went 162 mph. This means that the plane flew against the wind
Let x = the speed of the plane
Let y = the speed of the wind
when flying with the wind,
x + y = 198 - - - - - - -1
When flying against the wind,
x - y = 162 - - - - - - - -2
Subtracting equation 2 from equation 1,
y - - y = 198 - 162
2y = 36
y = 36/2 = 18 miles per hour
x = 198 - y = 198 -18
x = 180 miles per hour
