Suppose I look at a collection of 10 students and calculate the mean and standard deviation of their GPAs. No one in this group has a 4.0. Then I take another 10 students at random and find that one of them has a 4.0. How surprised should I be by this? Knowing the mean and standard deviation of the first group, how many non-4.0 students should I expect to see before finding one with a 4.0?
Edit: In hindsight, I can see that maybe the discrete nature of a GPA calculation and the fact that a 4.0 represents a maximum possible bound may complicate the issue. If it simplifies things, assume continuously valued variables with no upper or lower bounds.
Links to suggested references are welcome!