Question

1. a statistics teacher grades using z - scores. on the second major exam of the trimester, a student receives a grade with a z - score of - 1.3. what is the correct interpretation of this grade? (a) the students grade went down 1.3 points from the first exam. (b) the students grade went down 1.3 points more than the average grade went down from the first exam. (c) the student scored 1.3 standard deviations lower on the second exam than on the first. (d) the student scored 1.3 standard deviations lower on the second exam than the class average on the first exam. (e) the student scored 1.3 standard deviations lower on the second exam than the class average on the second exam.

Explanation:

The z - score represents the number of standard deviations a data - point is from the mean. A negative z - score of - 1.3 means the student's score is 1.3 standard deviations below the mean of the second exam.

Answer:

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