Answer:
Vp = 358.3m/s
Explanation:
Taking
North: UP
South: DOWN
East: RIGHT
West: LEFT
In the attachment, the velocity vector triangle is shown for the scenario. the triangle formed is a right angled triangle.
We can apply the Pythagora's Theorem.
370 ^ 2 = 92.5^2 + Vp^2 (Vp: plane velocity relative to ground)
Vp = sqr.rt(370^2 - 92.5^2)
Vp = 358.3m/s