Average is an important concept in statistics. The average in primary school mathematics generally refers to the arithmetic average, that is, the quotient obtained by dividing the sum of a set of data by the number of this set of data. In statistics, arithmetic mean is often used to represent the overall level of statistical objects, and it is a statistic that describes the position in the data set.

It can be used not only to reflect the general situation and average level of a group of data, but also to compare the data of different groups and see the differences between groups.

The nature of the average:

1, the average value is greater than the minimum number and less than the maximum number.

2. The average value is not necessarily the number in this set of data.

3. All data should participate in the calculation, including 0.

4. The farther a data is from the average, the greater the influence on the average.

5. If a data is equal to the average value, it will not affect the average value of a group of data.

6. All the data are fluctuating on average, and the sum of their deviations is equal to 0.

7. The average does not make all the data equal.

8. The average value is the result of sharing the total amount of each data on average.

9. The average value reflects the characteristics of a set of data, not the characteristics of each of them.