Question

If a student scores 90 points on a biology test with a mean of 83.2 and a standard deviation of 3.7, the student's z-score is __

a. 90-83.2/3.7
b. 83.2-90/3.7
c. 90+83.2/3.7
d. 90-83.2-3.7/3.7

Answer 1

The student's z-score is calculated using the formula z = (X - μ) / σ, resulting in the correct answer being option a. 90-83.2/3.7. A z-score quantifies how many standard deviations a score is from the mean.

Step-by-step explanation:

To calculate the z-score for a student's biology test score, we use the formula z = (X - μ) / σ, where X is the score, μ is the mean of the scores, and σ is the standard deviation.

In the case of the student who scored 90 on a test with a mean of 83.2 and a standard deviation of 3.7, the calculation would be:

z = (90 - 83.2) / 3.7

So the correct answer is a. 90-83.2/3.7.

A z-score represents the number of standard deviations a score is from the mean. Positive z-scores indicate scores above the mean, while negative z-scores indicate scores below the mean. This allows for comparison of scores from different data sets with different means and standard deviations.