Need a maths wizz

[Aussie John]

Hi I have a database (see attached) which assesses the condition of a room. There will be a number of categories but for simplicity have only shown two.

What I need some sort of weighted average.

in the example finishes are given an importance of 5 out of 10. and safety 10 out of 10.

I want the weighted value to calculate as follows;

1 rating --calc-->1

5 rating--calc-->5

3-4 rating--calc--->somewhere in between dependant on the importance

I think I need a log scale.

The idea is if all the categories are rated as 5 then the result average must be 5 (likewise 1 at opposite end).

Probably trying to do something mathematically inept but…

Thanks

test.fp7.zip

[comment]

I don't know - it seems simple enough to me. Each category has a value and a weight. You multiply each value by its weight, sum the results, and divide by the sum of weights.

test.fp7.zip

[Aussie John]

Thanks - a heavy head cold wasnt helping me much yesterday