Under the 3-sigma rule, 96% of observations would be within how many standard deviations from the mean?
A) 0
B) 1
C) 2
D) 3

Question

Quizplus · Accepted Answer

According to the 3-sigma rule, 99.73% of observations would be within 3 standard deviations from the mean. Therefore, 96% of observations would be within 2 standard deviations from the mean (i.e. 99.73% - 68.27% = 31.46%, which is divided by 2 to get 15.73% on each side of the mean for a total of 31.46%). Thus, the answer is C) 2.

Under the 3-Sigma Rule, 96% of Observations Would Be Within