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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.

User Mrjohn
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1 Answer

11 votes

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.

User Aemkei
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