Question

An aeroplane has to go from a city A to another city B 500 km away in which B is north of A.The wind is blowing towards east at a speed of 20m/s.The air speed of aeroplane is 40 m/s.The direction in which the pilot should head the plane to reach the point B is

Answer 1

draw a diagram. This is nice and easy, since you have a right triangle. The distance traveled by the plane in t hours must form the hypotenuse of the triangle, so

(40t)^2 = (20t)^2 + 500^2
t = 25/√3 = 14.434 hours.

Now you can figure the distance and the angle θ (west of north) such that tanθ = 20t/500

Answer 2

Is it ok to mix m and km?