Lyle was a careful craftsman, but he wasn't very
creative. For example, he only sold two types of
wooden benches: stained and unstained. The un-
stained benches cost $20 each, and the stained
cost $32 each. If Lyle sold 21 benches last month
(stained and unstained combined) and collected a
total of $600, how many unstained benches did he
sell?

Whats the name of the vertical axis

The larger of two number is 4 less than twice the smaller number. the sum is 41. find the numbers

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.