A container ship is travelling at a speed 15 knots in a SE direction. It is a distance of 20 nautical miles due north of a small pilot boat which can travel at a speed of 25 knots. In what direction must the pilot boat steer in order to meet the container ship?
[Sailors measure distances in nautical miles which are slightly longer than land miles. They measure speeds in knots. 1 knot is 1 nautical mile per hour]