Math Help Forum - View Single Post - Calculating Percentages using Mean and Standard Deviation.

ANDS! · #8 July 29th, 2009, 06:49 PM

Quote:

Originally Posted by topic

what kind of math is this exactly??

Just math.
Forumla wise, we define the standard deviation "s" as:

$s=\sqrt{\frac{\Sigma(x-\bar{x})^{2}}{n-1}}$

where $s$ is the standard deviation, $x$ is our individual values in the sample, $\bar{x}$ is our mean of the sample, and $n$ is the total number of values in our sample data set.