Calculating Standard Deviation from Age Data

In a statistical study, the ages of a sample of 30 individuals were recorded as follows:

21, 25, 22, 23, 29, 30, 24, 22, 30, 27, 26, 25, 24, 26, 29, 25, 30, 31, 28, 27, 30, 31, 31, 33, 30, 29, 26, 24, 22, 21

Calculate the standard deviation of the ages. Use the following formula for the standard deviation:

$S =\frac{ ext{sqrt}igg(\frac{ ext{sum of }(x_i - ar{x})^2}{n}igg)}$ where $ar{x}$ is the mean of the ages and $n$ is the number of observations.