Afamily is trying to pick from different shades of paint for their living room. they have narrowed it down to three different blues and six different greens. the family decides to just randomly select a color from these. what is the probability they will pick a shade of blue. answer the question in decimal form to the nearest percent. !

F(n + 1) = f(n) – 8. if f(1) = 100, what is f(6)?

The base of a triangle exceeds the height by 9 inches. if the area is 180 square inches, find the length of the base and the height of the triangle.

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.