hello michele, I state that I understand less than t?, for? I managed by doing a few tests to understand how it gets to that 331, I try to explain: I open the calculator in windows 7 I set the cue ball on the hex so I've written 1cd064 - 1cc606 = a5e / 8 = 14b by resetting the cue ball on dec is out of the famous 331 ; the result ( 331) you get both, if you write the numbers with the calculator is if you do it with the keyboard, but first you have to perform the subtraction, and only after you've clicked = you need to perform the division if no is not 331. I hope I have been of help hello