How it is calculated
The weight must be greater than zero. A weight of zero would turn the line off, so such lines are not accepted.
Mean = sum(value × weight) / sum of weights
Where the numbers come from
- Numbers and weights
Example
“10 1” and “20 3” give (10 + 60) / 4 = 17,5.
Questions
How is it different from the ordinary mean?
A plain mean treats every number alike. Here you can give some of them more weight.
Percents as weights?
Yes, when the numbers are positive. There is no need to divide by 100: the calculator scales by the ratio of the sums.
Negative values?
The numbers themselves may be negative; the weights may not.