Question

On a standardized exam, the scores are normally distributed with a mean of 300 and a standard deviation of 40. Find the z-score of a person who scored 370 on the exam.

Answer 1

z = (X − μ) / σ = (370 − 300) / 40 = 70 / 40 = 1.75

So the score 370 is 1.75 standard deviations above the mean.