The speed on the plane is 104mph while that of the wind is 78mph
The formula for calculating distance is expressed as:
Speed = Distance/Time
If the plane is flying with the wind;
3(r+ w) = 312
r + w = 104 ................... 1
If against the wind
4(r - w )= 312
r- w = 78 .................. 2
Add both equations
2r = 104 + 78
2r = 182
r = 91
Since r + w = 104
w = 104 - 91
w = 13
Speed on the plane = r + w = 91 + 13 = 104mi/hr
Speed on the wind = 91 - 13 = 78mi/hr
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