Your vessel is on a course of 272°T at 15 knots. At 2113 a light bears 245.5°T, and at 2120 the light bears 227°T. At what time and at what distance off will your vessel be when abeam of the light?

Correct Answer: Option A — 2127, 1.8 miles

Using standard Bowditch relative bearing formulas for running fixes, the distance run between observations establishes the triangle of positions. Solving the resulting right triangles gives an abeam distance of 2.7 miles at the predicted time of 2135.