Ivan and Jorge were picking apples. Ivan said that for every 6 apples he picked, Jorge picked 4 apples. What are two possibilities of the number of apples that Ivan and Jorge picked?

Set $r$ is a set of rectangles such that (1) only the grid points shown here are used as vertices, (2) all sides are vertical or horizontal and (3) no two rectangles in the set are congruent. if $r$ contains the maximum possible number of rectangles given these conditions, what fraction of the rectangles in set $r$ are squares? express your answer as a common fraction.