X 1+X2+X3+Xn)/n=(A/B) divided by (a/b *1+b/1+a)-1= a-b/a+b, a special form of weighting. When the weights are equal, the arithmetic average is used to calculate the average.

average number

The quantity representing the trend in a set of data refers to the sum of all the data in a set of data divided by the number of this set of data. It is an indicator reflecting the trend of data concentration. The key to solve the problem of average application is to determine the "total amount" and the total number of copies corresponding to the total amount. In statistical work, average and standard deviation are the two most important measures to describe the trend and deviation of data sets.