Question 540909: If a plane can travel 500 miles per hour with the wind and 420 miles per hour against the wind, find the speed of the plane in still air. Answer by Theo(13342) (Show Source):
You can put this solution on YOUR website! p = speed of plane
w = speed of wind
p + w = 500 mph (traveling with the wind)
p - w = 420 mph (travfeling against the wind)
add these 2 equations together and you get:
2p = 920
divide both sides by 2 to get:
p = 460 mph.
this means that w = 40 mph.
with the wind, the speed is 460 mph for the plane plus 40 mph for the wind which equals a total of 500 mph.
against the wind, the speed is 460 mph for the plane minus 40 mph for the wind which equals a total of 420 mph.
number check out.
your answer is:
speed of the plane is 460 mph.
speed of the wind is 40 mph.
