Question: AP Stats 2006, again. An AP Statistics teacher had 63 students preparing to take the AP exam discussed in Exercise. Though they were obviously not a random sample, he considered his students to be "typical" of all the national students. What's the probability that his students will achieve an average score of at least 3?

Exercise: AP Stats 2006. The College Board reported the score distribution shown in the table for all students who took the 2006 AP Statistics exam.

Score          Percent of students

5                        12.6

4                        22.2

3                        25.3

2                        18.3

1                        21.6

a) Find the mean and standard deviation of the scores.

b) If we select a random sample of 40 AP Statistics students, would you expect their scores to follow a Normal model? Explain.

c) Consider the mean scores of random samples of 40 AP Statistics students. Describe the sampling model for these means (shape, center, and spread).