Provide an appropriate response.
-The mean score of a competency test is 82, with a standard deviation of 2. Between what two values do about 99.7% of the values lie? (Assume the data set has a bell-shaped distribution.)
A)Between 76 and 88
B)Between 80 and 84
C)Between 78 and 86
D)Between 74 and 90

Question

Quizplus · Accepted Answer

According to the empirical rule (68-95-99.7 rule) for a bell-shaped distribution, about 99.7% of the data lies within three standard deviations of the mean. Therefore, the range is mean ± 3(standard deviation) = 82 ± 3(2) = 82 ± 6, which gives us a range between 76 and 88.

Provide an Appropriate Response