This is driving me crazy (not anymore!)

[New001]

Mind Probe (http://ebaumsworld.com/mindprobe.html) (SFW)

??? What the hell is this? How is it doing it?

There has to be some easy explanation, but it's worked every single time against me.

[Alobar]

yeah, math is magical stuff

[kurosh]

The answer is always going to be a certain set of numbers (9, 18, 27, 36, 45, 54, 63, 72, 81) and those are all the same letter. The letters are randomized after every time you do it.

[New001]

Then explain it? /images/graemlins/frown.gif I feel really dumb not seeing how it's getting done.

[mythrilfox]

Only certain combinations of numbers can come out of those operations, namely all powers of 9. They just change the letters to correspond to all the powers of 9.

[New001]

Bah. Those bastards. Thanks.

[StevieG]

a two digit number xy is really 10x + y
then you subtract x and y
10x + y - x - y = 9x

your answer will always be a multiple of 9 (0,9,18...81)

each time the board loads, the symbols are assigned randomly, but all of the multiples of 9 up to 81 get the same symbol