Question

Frank and Marie set sail from the same point. Frank is sailing in the direction . Marie is sailing in the direction . After 11 hours, Marie was 5 miles due west of Frank. How far had Marie sailed?

Answer 1

Assuming that Marie and Frank are sailing with equals speeds, we will getthat they had sailed the same distance, but in different directions. We can
build the isosceles triangle with its vertices in starting point and points,
where Mary and Frank are after 11 hours. In this triangle we know the base and
opposite angle, so we can calculate the two other sides as base/sin(angle/2).



So we obtain (5/sin(10degrees)) miles = 28.7939 miles