Question

Use the population data set of the price, in dollars, of a milkshake at five different restaurants: 2, 4, 6, 9, 14.

The mean is 7.
Which of the following is the approximate standard deviation for the set?

Answer 1

The standard deviation of the set is 4.2

Explanation:

The standard deviation (sd) for the set is calculated as follows:

sd² = [(x1 - mean)² + (x2 - mean)² + ... ]/N

where x1, x2, et cetera are the values in the set and N is the number of elements in the set. Replacing with data:

sd² = [(2 - 7)² + (4 - 7)² + (6 - 7)² + (9 - 7)² + (14 - 7)²]/5

sd = √17.6

sd = 4.2