How does the amazing mind reader trick work?

Answer:
if you're talking about the one with the equation and all the symbols here is the trick: there are only certain answers to the equation. The symbol assigned to each one is different every time, but all the possible answers have the same symbol as each other, even though the symbols change every time.




The equation will result in numbers divisible by 9. (ie) 9,18,27,36,45, 54, 63, 72, 81, 90.
You can notice the same will not symbol will be in the above numbers. I need to know how it figures it out. The multiple of nine thing is right, but the same symbol thing isn't. Plaese answer this question/answer.


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Contributor: Zachary
First answer by ID1198150057. Last edit by Zachary Witherington. Contributor trust: 0 [recommend contributor recommended]. Question popularity: 3 [recommend question].