The average score of 100 students taking a statistics final was 70,with a standard deviation of 7. Assuming a normal distribution,what test score separates the top 5% of the students from the lower 95% of the students?
A)81.55
B)90.00
C)83.72
D)78.96

Question

Quizplus · Accepted Answer

To find the score that separates the top 5% from the lower 95%, we need to find the z-score that corresponds to the 95th percentile, which is approximately 1.645. Using the formula: score = mean + (z-score * standard deviation), we get 70 + (1.645 * 7) = 81.515, which rounds to 81.55.

The Average Score of 100 Students Taking a Statistics Final