In a hearing test, subjects estimate the loudness (in decibels) of sound, and the results are (mean = 70):
68, 67, 70, 71, 68, 75, 68, 62, 80, 73, 68

-What is the variance?
A)18
B)4.73
C)22.40
D)324
E)6.76

Question

In a hearing test, subjects estimate the loudness (in decibels) of sound, and the results are (mean = 70):
68, 67, 70, 71, 68, 75, 68, 62, 80, 73, 68

-What is the variance?
A)18
B)4.73
C)22.40
D)324
E)6.76

Quizplus · Accepted Answer

Variance is calculated by finding the average of the squared differences from the mean. The squared differences from the mean (70) are: 4, 9, 0, 1, 4, 25, 4, 64, 100, 9, 4. The average of these squared differences is 22.40.

In a Hearing Test, Subjects Estimate the Loudness (In Decibels)