Jon weights 148 lbs and hopes to gain 2 lbs a week . matt weighs 193 lbs and hops to l lb a week . how many weeks until they weigh the same

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.