Arithmetic mean is calculated by adding all the numbers in a given set and then dividing by the total number of items within that set. Learn different arithmetic mean formulas used for different types of data. The arithmetic mean or mean is the simplest way to calculate the average for the given set of numbers. It is classified into two different types, namely simple arithmetic mean and weighted arithmetic mean. Learn how to calculate the arithmetic mean of a set of observations using the formula X = ΣX n X = Σ X i n, where i varies from 1 to n. See solved examples and FAQs on arithmetic mean formula in statistics. Sum of all of the numbers of a group, when divided by the number of items in that list is known as the Arithmetic Mean or Mean of the group. For example, the mean of the numbers 5, 7, 9 is 4 since 5 + 7 + 9 = 21 and 21 divided by 3 [there are three numbers] is 7.
