Mark is a Stats 250 GSI who would like to report a measure of center for scores on the first exam. The mean score for his lab section was 77.46 points and the median was 84 points. One of Mark's students did not take the exam and received a zero. Since Mark knows this score will not count against the student, he removes the score of zero from his data.

How will the mean test score change if the grade of 0 is not included?

If there is an outlier test score of 20 points, which measure of center would you recommend that Mark report?