### The Mean or Average

In general, you caculate the mean or average of a set of numbers by adding them all up and divding by how many numbers you have. This can be defined as follows:For a set of numbers, {x_{2}, x_{3}, ... x_{j}} the mean or average is the sum of all "x" divided by "j".

### Worked Examples of Calculating the Mean

Let's start with an easy example. Calculate the mean of the following set of numbers:1, 2, 3, 4, 5

To do this, add up the numbers and divide by how many numbers you have (5 of them, in this case).

mean = (1 + 2 + 3 + 4 + 5)/5

mean = 15/5

mean = 3

Pretty easy, right? Here's another example of calculating the mean.

Calculate the mean of the following set of numbers:

25, 28, 31, 35, 43, 48

How many numbers are there? 6. So, add together all of the numbers and divide the total by 6 in order to get the mean.

mean = (25 + 28 + 31 + 35 + 43 + 48)/6

mean = 210/6

mean = 35

### Learn More

How To Calculate Standard DeviationCalculate Mean, Median, Mode, and Range

Accuracy and Precision