Key Terms Use the vocabulary terms listed below to complete each statement in Exercises 1-4. statistic mean median mode 1. To find the by the number of data items. 2. The mean is an example of a 3. The often. 4. The of a set of data, we add the numbers and then divide a number describing a set of data. of a set of data is the number or numbers that occur most is the middle number or the average of the two middle numbers in a list that has been ordered from smallest to largest.