Question

An AP Statistics teacher grades using z-scores. On the second major exam of the

grading period, a student receives a grade with a z-score of -1.3. What is the
correct interpretation of this grade?
O The student's grade went down from 1.3 points from the first exam.
The student's grade went down from 1.3 points more than the average grade went
down from the first exam.
The student scored 1.3 standard deviations lower on the second exam than on the
first exam.
The student scored 1.3 standard deviations lower on the second exam than the class
average on the first exam.
The student scored 1.3 standard deviations lower on the second exam than the class
average on the second exam.

Answer 1

E. The student scored 1.3 standard deviations lower on the second exam than the class average on the second exam.

Explanation:

Whenever we have a negative z-score, this means that the raw score is a certain standard deviation below the mean average.

From the above question, we are told that:

An AP Statistics teacher grades using z-scores. On the second major exam of the grading period, a student receives a grade with a z-score of -1.3.

This means the students score in the second major exam is 1.3 standard deviations below the average score in the second major exam.

Hence, according to the options given in the above question, the correct interpretation of this grade is

The student scored 1.3 standard deviations lower on the second exam than the class average on the second exam.

Option E is the correct option.