Definition of the arithmetic mean is the sum of the observed values, or the values of the samples in all surveys. The value of the data, and then divided by the number of data samples.
Defined as the arithmetic mean is the sum of the value or the value of the sample derived from a survey of all the data and dividing by the total number of data samples.
The definition, mean, is the sum of the observations or the value of the samples from the value of the information, then every divided by the number of samples of the data.