Note that this question has been adapted from Freedman, Pisani, and Purves (2007). Three instructors are comparing scores on their finals. Each class had 99 students.

For all three classes the range was the same: the top score was 99 and the lowest score was 1.

• In Class A, one student scored 1 point, another student scored a 99, and the rest got 50 points.

• In Class B, 49 students scored 1 point, one student got a score of 50, and 49 students got a score of 99.

• In Class C, the first student got a score of 1, the second student got a score of 2, the third student got a score of 3 … and so on, all the way through the 99th student who got a score of 99.

a) Which class had the highest mean, or were they all the same?

b) Which class had the biggest SD, or were they all the same?