3.2 Mean
Mean is the most common average. You have probably heard at one point someone say “on average”. For example, the mean life span in Sweden in 2005 was the following 
Source: SCB 
Imagine that you and a group of friends are going to compare your wages for a summer job with each other. The group of friends have the following hourly wages:
What is their mean wage?
To find out what the mean wage is, we add their salaries together and divide the sum by the number of wages, in this case 5. The calculation looks like this:
Mean = 
55kr + 60kr + 70kr + 80kr + 55kr 
= 
320 
= 64 kr 


5 
5 
The group of friends mean wage is then 64 kr. 