You are underway on a course of 135°pgc at 15 knots, and you sight a lighthouse dead ahead at a range of 12.5 miles at 1145. What course would you steer to leave the lighthouse 3.0 miles off your port beam?

Correct Answer: Option B — 149°pgc

Chart work and piloting principles require constructing a triangle of positions involving initial range, course, and desired passing distance. Solving the geometry for the offset track yields a course to steer of 149°pgc.