this one really was perplexing me until i figured out the formula...i knew what it was basically, but then i realized ...take any 2 digits and subtract them from the whole number like that, and you will ALWAYS get a # divisible by 9... and the 0-99 numbers with symbols,, not all of them are possible answers..you cant get just ANY of them as your answer. But of the possible answers, they all have the same symbol..and of course the symbols change every time. Sorry for stating the obvious, but im sure SOMEONE hasnt figured it out yet. lol