#### Definition

- The mean is a method of calculating the average of a set of numbers.
- To calculate the mean, find the sum of the numbers and then divide by the count.

#### Example

- Find the mean of the following numbers:
`[4, 7, 10]`

```
sum = 4 + 7 + 10 = 21
count = 3
mean = 21 / 3 = 7
```

#### Mathematical Definition

LaTeX formula:`\overline{x} = (\frac{1}{n})\sum_{i=1}^{n}(x_{i})`

#### Code (Python)

```
import numpy
values = [4, 7, 10]
mean = numpy.average(values)
print(mean)
```

#### Notes

- There are other types of mean, this one is called the 'Arithmetic Mean'.
- It is also called the 'Mathematical Expectation' and the 'Average'.