Flash Mind Reader

Flash Mind Reader

How does this work? I know there's a trick behind it, but I can't figure it out.

 

I did it twice and it didn't work.

 

Sometimes it doesn't work, but for me and my roomate it's worked almost the whole time.

I just want to know what the trick behind it is.

 

Many numbers have the same symbol. It's just chance after that.

 

Nope, if you look at the numbers that have the same symbols... for example 54 is one of them, it's always the same symbol as 54. I'm betting that there's some mathematical trick to figure out how many numbers it could be, and all of those numbers that are possible are the same symbol and the one that shows up...


EDIT: I think I've figured out the numbers that are always the symbol
0 9 18 27 36 45 54 63 72 81

Now, some math genius( AmazingB)come in and figure it out. If anyone comes up with an answer that isn't one of the above (like the people who said it was wrong for them) post it. This is intriguing me.

 

There are only a several possibilities of numbers to be chosen. For instance

91...9+1 = 10...91-10=81
92...9+2 = 11...92-11=81
93...9+3 = 12...93-12=81
.
.
.
10...1+0 = 1....10-1=9
11...1+1 = 2....11-2=9
.
.
.

So, the only possibilities end up being:

9, 18, 27 ,36 ,45, 54, 63, 72 ,81
(All multiples of 9)

All the others can never be chosen. Also, these multiples of 9 (only up to 81) have the same symbol. So, it always works.

EDIT: The theory behind the number scheme:

Let

(m*10)+n

be any two-digit number. Where n and m are any integer from 0 to 9.

If we add the value of the first digit with the value of the second digit, we have

m+n

So the difference between the two is

[(m*10)+n] - (m+n)

=(10m-m) + (n-n)

=9m + 0

Since m is any integer from 0 to 9, then 9m is any multiple of 9 from 9 to 81.

 

Worked for me every time.... creepy

 

so, I guess the people who said it didn't work made a mental math error?

 

Thanks, D_OT. I think I get it now.

 

Actually, nevermind.

 

Actually I should clarify,

9m is any multiple of nine from 0 to 81.

 

Yup. I knew how it worked.

Go me.

 

go me! i figured out the tric without reading the thread.