Adjusting hydrometer readings

Northern Brewer General
1

So I was reviewing my notes for a black ale that I’m making and realized that I took the hydrometer reading for the OG with just the undiluted wort. Is there anyway I can adjust this reading to after I added my top-off water? It was roughly 4 gallons of wort with 1.5 gallons of water as a top off. OG was initially read at 1.060, but I did some rough math and am guessing it was actually something like 1.055. Is there a more absolute system so I can accurately project my gravities?

The gravity right now after 19 days of fermentation @ 65-68*F is 1.012 (using WLP 029 German/Kolsch yeast).

2

Use the ratio of the volumes like this:

60 x 4 / 5.5 = 43 or 1.043 for the diluted OG.

3

Thanks Shade.

4

The beer as it stand right now is a little sweeter than I’d want it to be. I can’t remember if it’s okay to add corn sugar while it’s in the fermenter to boost gravity.