I have a set of statistics that I need to find the overall ratio to. This example will work with only two items so I'll write them down:
A | B --------- 12 | 5 6 | 2
The total ratio needs to be worked out as:
(12 + 6) / (5 + 2)
The problem however, is that the ratio of each row can be modified by a user, meaning the source values A and B can only be used as "default" sources.
To allow partial modification of the entire set by modifying specific ratios I saved the ratios of each individual row like this:
A | B | R ------------- 12 | 5 | 2.4 6 | 2 | 3
I then attempted to come to the same overall ratio (since at the moment these ratios are un-modified), however getting the mean average did not work:
(2.4 + 3) / 2 = 2.7
The fact that the ratios can be modified make the original source data completely irrelevant in the overall statistic, but I still need to arrive at
2.57, is this possible?
I am prepared to change the type of modifiable information stored against each row, providing it can still be used to represent a percentage.