Unknown008
Mar 1, 2011, 07:19 AM
It's the sum of all the three things, and then you divide by 3.
In mathematical notation, let's say you have things in x.
x_1, x_2, x_3, ... x_n
You have therefore n things. The average (or mean) is then:
\frac{x_1, x_2, x_3, ... x_n}{n} = \frac{\Sigma x}{n}
This is just some extra information :)