The mean (average) of a data set is found by adding all numbers in the data set and then dividing by the number of values in the set. The median is the middle value when a data set is ordered from least to greatest. The mode is the number that occurs most often in a data set.
The median is the middle point in a dataset—half of the data points are smaller than the median and half of the data points are larger. To find the median: Arrange the data points from smallest to largest. If the number of data points is odd, the median is the middle data point in the list.
the range of a set of data is the difference between the largest and smallest values.