# Mystical Ball

http://www.mysticalball.com/

this is weird, it turned out to be quite accurate when i play with it.
How? How they do tat? Any theory behind this?

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matthyaouw
Gold Member
Its simple maths. If you do the sum it gives you, there are realatively few answers that it can give, and all these answers are assigned the same symbol on the chart, and then brings up that symbol when you click it.

Try working out more than one number before you click on the ball, and see if they all come up as the same symbol.

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DaveC426913
Gold Member
An even simpler way to root out the trick here is to try the same number several times in a row. Try doing the example (23) several times. Your answer is always 18. But do you notice anything odd? On any given try, 18 in the chart is always the symbol that appears in the ball.

The key then is to realize that, no matter what initial number you picked, only certain answers will apply:

Code:
99 : 9+9 = 18 : 99-18=[B]81[/B]
98 : 9+8 = 17 : 98-17=[B]81[/B]
97 : 9+7 = 16 : 98-16=[B]81[/B]
96 : 9+6 = 15 : 98-15=[B]81[/B]
...
90 : 9+0 =  9 : 99-9 =[B]81[/B]
89 : 8+9 = 17 : 89-17=[B]72[/B]
88 : 8+8 = 16 : 88-16=[B]72[/B]
...
80 : 8+0 = 8  : 80-8 =[B]72[/B]
Note that both 81 and 72 are the same symbol, as are 63, 54, 45 etc. This repeats all the way down to 0.

No matter what initial number you choose, it is going to result in one of those few special answers.
.

Danger
Gold Member
DaveC426913 said:
no matter what initial number you picked, only certain answers will apply
It's basically just a computerized version of one of the old stage 'mind-reader' tricks.

DaveC426913
Gold Member
Danger said:
It's basically just a computerized version of one of the old stage 'mind-reader' tricks.
Uh well, sure, but that doesn't really explain anything does it? :uhh:

rachmaninoff
Blindingly obvious. You have a two-digit number, xy in digit form. You substract the sum of the two digits,

xy - (x + y) (xy means two digits, not multiplication)
=(xy - y) - x
=x0 - x
=x * (10 - 1)
=9 * x
qed

So the only possible numbers are 9, 18... 81, and they all have the same * symbol.

Danger
Gold Member
DaveC426913 said:
Uh well, sure, but that doesn't really explain anything does it? :uhh:
I didn't have to explain anything. I was just elaborating upon your post. :tongue: