SOLUTION: A plane flies 470 miles with the wind and 310 against the wind in the same length of time. If the speed of the wind is 40 mph find the speed of the plane in still air.

Question 764208: A plane flies 470 miles with the wind and 310 against the wind in the same length of time. If the speed of the wind is 40 mph find the speed of the plane in still air.
Answer by Cromlix(4381) (Show Source): You can put this solution on YOUR website!
Speed with wind = x + 40
Speed against wind = x - 40
470/x + 40 = 310/x - 40
Cross multiply
470(x - 40) = 310(x + 40)
470x - 18800 = 310x + 12400
470x - 310x = 12400 + 18800
160x = 31200
x = 195mph in still air.
Hope this helps.
:-)
RELATED QUESTIONS
A plane flies 460 miles with the wind and 310 miles against the wind in the same length... (answered by lwsshak3)

a plane flies 450 miles with the wind and 300 miles against the wind in the same length... (answered by Fombitz)

A plane flies 450 miles with the wind and 350 miles against the the wind in the same... (answered by lwsshak3)

A plane flies 420 miles with the wind and 350 miles against the wind in the same length... (answered by Paul)

A plane flies 500 miles with the wind and 340 miles against the wind in the same length... (answered by Nate,funmath,stanbon)

A plane flies 440 miles with the wind and 320 miles against the wind in the same length... (answered by ankor@dixie-net.com)

A plane flies 480 miles with the wind and 320 miles against the wind in the same length... (answered by checkley75)

A plane flies 400 miles with the wind and 320 miles against the wind in the same length... (answered by checkley71)

A plane flies 500 miles with the wind and 350 miles against the wind in the same length... (answered by HyperBrain)