Final answer:
The z-score of a person who scored 285 on the exam is approximately -0.3, which means the score is 0.3 standard deviations below the mean.
Step-by-step explanation:
To find the z-score of a person who scored 285 on the exam, we can use the formula:
z = (x - μ) / σ
where:
- z is the z-score
- x is the individual score
- μ is the mean of the distribution
- σ is the standard deviation of the distribution
Plugging in the values, we have:
z = (285 - 300) / 50 = -0.3
Therefore, the z-score of a person who scored 285 is approximately -0.3. This means that the score is 0.3 standard deviations below the mean.