At maximum speed, an airplane travels 1720 miles against the wind in 5 hours. Flying with the wind, the plane can travel the same distance in 4 hours. Let x be the maximum speed of the plane and y be the speed of the wind. What is the speed of the plane with no wind?

Question

anonymous · Answer

1720/5 = Vplane - Vwind  (1)
1720/4 = Vplane + Vwind  (2)

anonymous · Answer

344 = x - y
430 = x + y
add equations

774 = 2x
x = 387mph

anonymous · Answer

1720 = 5(x - y)
1720 = 4(x + y)

anonymous · Answer

Thank you :D

anonymous · Answer

x - y = 344
x + y = 430
2x = 774
x = 387
y = 430 - 387 = 43
Maximum speed of aircraft is 387 mph, wind speed is 43 mph.