The sum of the data, divided by the number of data items.
EX: 81 + 77 + 92 + 89 = 339
339 � 4 = 84.75
The mean of 81, 77, 92, and 89 is 84.75
MEDIAN:
The middle number in a set of ordered data.
4, 7, 9, 13, 25
9 is in the middle, so 9 is the Median!
MODE:
The data item that appears most often.
EX: 5, 7, 7, 7, 9, 11, 13, 13, 15
7 is the Mode because it appears the most often.
** If all data items appear the same number of times, there is no mode. **