A gym container holds 50 balls of two sizes and two colors. Twenty-two balls are large and red, 12 balls
are small, and 25 balls are green. How many of the balls are small and green.
Since only 12 balls are small, each color has 25, 22 red balls are large - that leaves 3 red balls that are small. 12 small balls total less the 3 red small balls - that leaves 9 green small balls.
