The mean is a measure of centre which is often regarded as the ‘average’. The mean of a data set is given by:

$\bar{x}= \frac{\sum{x}}{n}$

• $\bar{x}$= mean of the data values
• $\sum{x}$ = sum of all the data values
• $n$= total number of data values

### Application

Consider the set of data

${3,7,1,9,12}$

The mean of this set of data is

$mean = \frac{3+7+1+9+12}{5} = 6.4$