Mean

In statistics, mean has two related meanings:

Harmonic mean

The harmonic mean is an average which is useful for sets of numbers which are defined in relation to some unit, for example speed (distance per unit of time).

Related Topics:
Harmonic mean - Unit - Speed

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: ar{x} = rac{n}{sum_{i=1}^n rac{1}{x_i}}

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An example

An experiment yields the following data: 34,27,45,55,22,34

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To get the harmonic mean

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• How many items? There are 6. Therefore n=6
• What is the sum on the bottom of the fraction? It is 0.181719152307
• Get the reciprocal of that sum. It is 5.50299727522
• To get the harmonic mean multiply that by n to get 33.0179836513