Question

Suppose the test scores of students in a class are normally distributed with a mean of 85 and a standard deviation of 4. What is the z-score for a student that scored 79 on a test

A. -4
B. -1.5
C. 1.5
D. 4

Answer 1

Answer:

B

Step-by-step explanation:

Converting it to z, we can use the formula of z-score:

z-score = $\frac{x-\mu}{\sigma}$

Where

x is the value we are checking for (here, x = 79)

$\mu$  is the mean, which is 85

$\sigma$ is the standard deviation, which is 4 now

Let's plug the information into the formula and solve for the answer:

$\frac{x-\mu}{\sigma}\\\frac{79-85}{4}\\-\frac{6}{4}\\-1.5$

B is the correct answer.