In addition to being measured by central tendency, group data can be measured by variability in descriptive statistics. The standard deviation from the mean is a measure of average deviation from the mean in a set of scores. What is the standard deviation of the following set? 2, 5, 20
A)9
B)18
C)13.6
D)62

Question

Quizplus · Accepted Answer

13.6 is the standard deviation of those scores. To calculate standard deviation, first find the mean of the numbers, which is 9. Then subtract the mean from each number in the set, which gives you -7, -4, 11. Square each of those numbers to get 49, 16, 121. Add those three, 186, and square root that number.

In Addition to Being Measured by Central Tendency, Group Data