Dilution Calculations

[Digby Swift]

Can anyone tell me the way to calculate the resulting extract from mixing two worts?

For example I need to calculate:

31.1 Barrels at 25 lbs per barrel
+
11 barrels at 8.6 lbs per barrel

Are the calculations different when working it out using SG values?

I know the answer to this as I used beersmith but can someone tell me how you do it?

[Eadweard]

Are you talking brewers lbs per barrel here? I find extract easiest in litre degrees, so one barrel is 163.7 l, 25 brewers lbs per barrel = o.g. 1069.5, 8.6 brewers lbs per barrel = 1024

31.1 barrel x 163.7 litres x 69.5 brewers degrees = 353829 litre degrees

+

11 x 163.7 x 24 = 43217 litre degrees

=

Total litre degrees = 397046

Total volume = 6728 l

litre degrees/volume = og = 1059

Is this what you're after?

[Digby Swift]

Thanks that is what i'm after but do you know how to do it without converting into litres? How do you get the answer in lbs per barrel?

Does this work?

31.1 Barrels at 25 lbs per barrel
+
11 barrels at 8.6 lbs per barrel

so

(31.1 * 25 + 11 *8.6)/42.1 = 20.71 lbs/barrel

[Eadweard]

Yes, that's it.