On a standardized exam, the scores are normally distributed with a mean of 79 and a standard deviation of 20. Find the z-score of a person who scored 121 on the exam.

Question

asked Jul 14, 2023 6.0k views

1 Answer

Aemkei · Answer 1 · 2023-07-18T23:33:06+0000

Answer:

z = 2.1

Explanation:

$z=(x-\mu)/(\sigma)\\ \\z=(121-79)/(20)\\ \\z=(42)/(20)\\ \\z=2.1$

This tells us that the person's score of 121 places them 2.1 standard deviations above the mean score of 79.