Finding an average of a set of numbers is also known as finding the mean. The only difference between decimals and whole numbers is that decimals represent a portion of a whole number, which may or not be combined with a whole number itself. If you want to find the average of a set of decimals, you only need to use basic mathematical skills such as adding and dividing.
Add the list of decimals. For example, consider the following list: 0.45, 1.6, 2.9 and 0.84. Added together, these values equal 5.79.
Count the number of decimals in the set that you added. In this example, you added four decimal figures.
Divide the total from Step 1 by the number of decimals in your set (as determined in Step 2). In this example, you would divide 5.79 by 4 to get 1.4475. This is the average for your set.