Bart scored 86 on his statistics midterm, and the class average was 85.What would his deviation and z score be in a distribution of the midterm grades?
A) It would be -1.
B) It would be 0.
C) It would be negative.
D) It would be positive.

Question

Quizplus · Accepted Answer

The deviation would be Bart's score minus the class average:

86 - 85 = 1

Since Bart scored above the class average, his deviation is positive.

To calculate the z-score, we use the formula:

z = (x - μ) / σ

where x is the individual score, μ is the population mean (or in this case, the sample mean), and σ is the population standard deviation (or in this case, the sample standard deviation, which we do not have).

However, since we know that Bart's deviation is 1 and that the average deviation is 0, we can use the simplified formula:

z = deviation / standard deviation

Since Bart's deviation is 1 and we do not have the standard deviation, we cannot calculate the exact z-score. However, we do know that the z-score would be positive since he scored above the average. Therefore, the best choice is D: It would be positive.

Bart Scored 86 on His Statistics Midterm, and the Class