40 potential navy seals compete for 30 open spots by treading water. the histogram shows the length of time the recruits tread water. how many recruits tread water for more than 6 hours?

32
30
24
23

White shapes and black shapes are used in a game. some of the shapes are circles. while the rest are squares. the ratio of the number of white shapes to the number of black shapes is 5: 11. the ratio of the number of white cicrles to the number of white squares is 3: 7. the ratio of the number of black circles to the number of black squres is 3: 8. work out what fraction of all the shapes are circles.