well, we know each car holds 5 folks, we know also that the "interior" angles of the wheel sum up to 7740
º, so hmm how many cars on that "regular polygon" wheel anyway?
well

so the ferris wheel has 45 sides, is a polygon of 45 sides... that means it has 45 cars, each car can hold 5 folks, so it can hold a maximum of 45 *5