To determine the variance of a sample we can use the following formula:
where
is the mean of the dataset.
The standard deviation is the square root of the variance.
Recall that the mean of a dataset is the sum of the number divided by the number of numbers, therefore, the mean of the given dataset is:
Substituting the above result in the formula for the variance, we get:
Therefore, the standard deviation is:
Answer:
Variance:
Standard deviation: