On a standardized exam, the scores are normally distributed with a mean of 75 and a standard deviation of 10. Find the z-score of a person who scored 45 on the exam.

To find the z-score of a person who scored 45 on the exam, we use the formula:

z = (x - μ) / σ

where:
x = the individual's score (45)
μ = the mean (75)
σ = the standard deviation (10)

Plugging in the values, we get:

z = (45 - 75) / 10
z = -30 / 10
z = -3

Therefore, the z-score of a person who scored 45 on the exam is -3.