Problem:
On a certain math exam, of the students got points, got points, got 85 points, got points, and the rest got points. What is the difference between the mean and the median score on this exam?
Answer Choices:
A.
B.
C.
D.
E.
Solution:
The percentage of students getting points is
so the mean score on the exam is
Since fewer than half of the scores were less than , and fewer than half of the scores were greater than , the median score is . The difference between the mean and the median score on this exam is .
Answer: .
The problems on this page are the property of the MAA's American Mathematics Competitions