I use this site to figure out the calcs:

http://home.sunlitsurf.com/~mshapiro/convert.html

There is also a Calulator you can download

Chad
Lazy Hill Wine Log: http://www.chadandtrish.com/winelog

"Brian" > wrote in message news:<C%0Cc.3977$Pa4.3284@lakeread04>...
> Just trying to predict the end result of additions of various things to a
> must.
>
> Is the relationship:
>
> [(vol A x Brix A) + (vol B x Brix B)] / (vol A + vol B)
>
> linear?
>
> In other words:
>
> If I have 1 gallon of a solution at 10 Brix and 3 gallons of another
> solution at 20 Brix, should the resultant volume and sweetness be: 4 gallons
> at 17.5 Brix?
>
> Brian