[Mathematics] Deviation

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Deviation

The deviation is a value indicating how far away from the average.

For example, if there are two numbers 90 and 100, the average is 95, the deviation of 90 is -5, and the deviation of 100 is 5.

And since the sum of the deviations is always 0, if you add the deviations of 90 and 100, -5 and 5, it becomes 0.

Deviation is used when calculating Variance and Standard Deviation.