Questions: A student in a statistics class took the midterm and was told by the professor that her z-score for the exam was 1.5. What does this tell us about the student's score relative to the rest of the class?
Her score is 1.5 standard deviations below the mean
Her score is 1.5 standard deviations above the mean
Her score is 1.5 points below the mean
Her score is 1.5 points above the mean
Her score is 15% higher than the class mean
Her score is 15% lower than the class mean
Transcript text: A student in a statistics class took the midterm and was told by the professor that her 2-score for the exam was 1.5. What does this tell us about the student's score relative to the rest of the class?
Her score is 1.5 standard deviations below the mean
Her score is 1.5 standard deviations above the mean
Her score is 1.5 points below the mean
Her score is 1.5 points above the mean
Her score is $15 \%$ higher than the class mean
Her score is $\mathbf{1 5 \%}$ lower than the class mean
Solution
Solution Steps
Step 1: Understanding the Z-Score
The student's z-score is given as \( z = 1.5 \). The z-score indicates how many standard deviations a data point is from the mean of a distribution. A positive z-score means the score is above the mean.
Step 2: Interpretation of the Z-Score
Since \( z = 1.5 \), we can conclude that the student's score is \( 1.5 \) standard deviations above the mean. This can be mathematically expressed as:
\[
\text{Score} = \mu + 1.5\sigma
\]
where \( \mu \) is the mean score of the class and \( \sigma \) is the standard deviation.
Final Answer
The student's score is \( \boxed{1.5} \) standard deviations above the mean.