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+# Mean, median and mode
+
+| Term   | Definition                                                                      | How to find                                                                                                                                                                                                                                                                                      | Example                                                                                                                                         |
+| ------ | ------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | ----------------------------------------------------------------------------------------------------------------------------------------------- |
+| Mean   | The average value of a set                                                      | <ol><li>Add up all values in the set to get the total sum of all values</li><li>Count the number of values in the set</li><li>Divide the total sum by the count</li></ol>                                                                                                                        | Given the {1, 5, 4, 7} set, its mean is (1+5+4+7)/4 = 17/4 = 4.25                                                                               |
+| Median | The value in a set which divides the set's upper half from the set's lower half | <ol><li>Arrange all values in the set from the lowest to the highest</li><li>If the number of values is odd, the median is the value in the middle of the ordered set</li><li>If the number of values is even, the median is the mean of the 2 values in the middle of the ordered set</li></ol> | <p>Given the {1, 5, 4, 7} set, its median is {1,4,5,7} = (4+5)/2 = 4.5</p><p>Given the {1, 5, 4, 7, 11} set, its median is {1,4,5,7,11} = 5</p> |
+| Mode   | The value(s) in a set that occurs the highest number of times                   | <ol><li>Count the amount of repetitions (frequency of appearance) of each value in the set</li><li>The value (or values if more than one) that appear most is (are) the mode of the set                                                                                                          | <p>Given the {1, 1, 4, 5, 7, 7, 2, 2, 2} set, its mode is 2</p><p>Given the {2, 3, 4, 6, 3, 7, 2, 1} set, its mode is 2 or 3</p>                |
+
+## Sources
+
+- [Mean, median, and mode review]
+- [Mean, median, mode calculator]
+
+<!--
+  References
+  -->
+
+<!-- Others -->
+[mean, median, and mode review]: https://www.khanacademy.org/math/statistics-probability/summarizing-quantitative-data/mean-median-basics/a/mean-median-and-mode-review
+[mean, median, mode calculator]: https://www.calculatorsoup.com/calculators/statistics/mean-median-mode.php