Question

On a standardized exam, the scores are normally distributed with a mean of 550 and a standard deviation of 50. Find the z-score of a person who scored 495 on the exam.

Answer 1

-1.1

Explanation:

The z-score formula is expressed as;

z = x - m/s

x is the sample size = 495

m is the mean score = 550

s is the standard deviation = 50

Substitute inti the formula;

z = 495 - 550/50

z = = -55/50

z = -11/10

z = -1.1

Hence the z score is -1.1