# Arithmetic Mean

## Arithmetic Mean

Quotient of the sum of the values in the distribution of a quantitative statistical characteristic by the number of values.

### Notations

• The arithmetic mean of a distribution is noted as: $$\overline{\textrm{x}}$$.
Some books prefer the notation $$\overline{\textrm{X}}$$.
• When it is necessary to distinguish between the mean of an entire population and the mean of a sample, the mean of the entire population is generally noted as: μ.

### Formula

If a distribution E includes the data $$x_1, x_2, x_2, x_3, x_4, …, x_n$$, then the arithmetic mean of E is given by:

$$\overline{\textrm{x}} = \dfrac{x_1 + x_2 + x_2 + x_3 + x_4 + … + x_n}{n}$$

### Examples

Consider the numbers: 3, 5, 7, 9, 11, 13.
The arithmetic mean of these numbers is: $$\overline{\textrm{x}}$$ = $$\frac{3\space +\space 5\space +\space 7\space +\space 9\space +\space 11\space +\space 13}{6}$$ = 8.