Your are on course 317°T at 13 knots. A light is bearing 22.5° relative at 0640. At 0659 the same light is bearing 45° relative. At what time should the light be abeam?

Question

Your are on course 317°T at 13 knots. A light is bearing 22.5° relative at 0640. At 0659 the same light  is bearing 45° relative. At what time should the light be  abeam?

Accepted Answer

Option A: 0712. Applying the Bowditch or standard relative bearing math, time interval from 0640 to 0659 is 19 minutes for a 22.5-degree change. Equal angle to abeam (45 degrees) takes an identical run time of 19 minutes, yielding 0712.