I put the formula for acid testing that Ibgloin posted recently in excel format. I did not know how to post as a excel link, so did a screen capture. For those of you with excel, you can set up a simple worksheet that only requires you to change the sodium hydroxide amount, and it does the rest.
If you have excel on your pc, just make a new spreadsheet and copy the formula shown in the TA column. it is: = (B1)*(B2)*(75)*(100)/(1000*(B3)). hope this helps