Question

On a standardized exam, the scores are normally distributed with a mean of 300 and a standard deviation of 50. Find the z-score of a person who scored 250 on the exam.

Answer 1

z = (x − μ) / σ = (250 − 300) / 50 = −50 / 50 = −1

So the score of 250 is 1 standard deviation below the mean (z = −1).