Hey there! Hello!
To find the mean of a set of numbers, you would need to add the numbers up and divide them by how many numbers are present. This is easier if you have access to a calculator, but it can certainly be done by hand.
5.6 + 7.4 + 5.4 + 8.0 + 1.4 = 27.8
27.8 / 5 = 5.56
Your final mean will be 5.56.
Hope this helped you out! :-)