There are 34 beads on Brenda's necklace. 24 of the beads are pink and the rest are purple. What is the ratio of the number of pink beads to the total number of beads?
10:24
10:20
24:34
24:10

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.