At maxuimum speed an airplane travels 2400 miles against the

At maxuimum speed an airplane travels 2400 miles against the wind in 6 hrs. Flying with the wind the plane travels the same distance in 5 hrs. Let X be the maximum speed of the of the plane and y be the speed of the wind, what is the speed of the plane with no wind

Solution

2,400/6=(x-y) mph against the wind
2,400/5=(x+y) mph with the wind
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2,400/6+2,400/5=2x
(5*2,400+2,400*6)/30=2x
(12,000+14,400)30=2x
26,400/30=2x
60x=26,400
x=26,400/60
x=440 mph is the speed of the plane in still air.
2,400/6=440-y
400=440-y
-y=400-440
-y=-40
y=40 mph is the wind speed
Proof:
2,400/5=440+40
480=480