What does the mean as in the math way of mean mean?

Answer 1

To get the arithmetic mean you add all the numbers up. Then, count the number of numbers you added, and divide the sum by the toal number of numbers.

So the arithmetic mean in math is the average of a set of numbers.

Example: (A+B+C+D+E) / 5

The geometric mean is calculated differently: You multiply all the numbers together (they must all be positive) and take the nth root of the product (where n is the count of the numbers multiplied)

Example: (A*B*C*D*E)1/5

The harmonic mean is something else again:

Example: 5 / (1/A + 1/B + 1/C + 1/D + 1/E)

There are a bunch of other means for other purposes too!