Mean, median, and mode are the most commonly used kind of "averages" in statistics. For numerical observations, the "mean" is the "average” that is calculated by adding up all the numbers and then divide by the number of observations. The "median" is the "middle" value in the list of observations. To find the median, observations are listed in numerical order and middle value is the median. The "mode" is the observation that occurs most frequently. If no number is repeated, then there is no mode for the list.