While doing a project for P. E. class, Ann researched the number of athletes competing in an international sporting event. How many countries have fewer than 90 athletes?
Stem | Leaf 
1 | 5, 8
2 | 4
3 | 2, 2, 6, 8
4 | 2, 3, 5, 9
5 | 0, 9
6 | 4
7 | 8
8 | 1, 4, 5, 7
9 | 0
Count all the leaves in the rows with stems 1, 2, 3, 4, 5, 6, 7, and 8.

You counted 19 leaves, which are blue in the stem-and-leaf plot above. 19 countries have fewer than 90 athletes.