# Mean

The **mean** is an average of at least two numbers. To determine this, all values are added and divided by the number.

The general formula for calculating the mean is:

$\frac{x_1+x_2+\dots+x_n}{n}$

$x$ ... values

$n$ ... number of values

### Example

Peter took part in a flea market on 4 different days and earned 15 €, 25 €, 9 € and 18 €. Calculate how much Peter earned on average in one day.

$\frac{15+25+9+18}{4}=\frac{67}{4}=16.75$

Peter earned an average of 16.75 € a day.