A vessel steams 640 miles on course 047°T from LAT 34°45'N, LONG 140°00'E. What are the latitude and longitude of the point of arrival by mid-latitude sailing?

Correct Answer: Option C — LAT 42°01'N, LONG 149°57'E

Mid-latitude sailing formulas determine the change in longitude (DLo) by dividing departure by the cosine of the mean latitude. With a distance of 640 miles and course 047°T, the calculated latitude difference and DLo result in a final position of LAT 42°01'N, LONG 149°57'E, consistent with Bowditch procedures.