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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

User Jake Braun
by
4.9k points

1 Answer

3 votes

Answer:

B

Explanation:

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

z-score =
(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:


(x-\mu)/(\sigma)\\(79-85)/(4)\\-(6)/(4)\\-1.5

B is the correct answer.

User John Himmelman
by
5.6k points