This is a mind reading exercise, and it must be done by following/performing each instruction very carefully.  After you finish the final instruction, write down your final number and draw a square around it.  Then see if you can discover the underlying principle of the game.
Instructions:

  • Think of a 2-digit number between 10 and 99, inclusive.
    (example, 39)
  • Add the number’s two digits together to create a sub-total.
    (example, 3 + 9 = sub-total of 12)
  • Create a final-total by subtracting the sub-total from your
    2-digit number.    (example, 39 – 12 = final-total of 27)
  • Think about your final-total and then find your final-total in the picture and then concentrate for at least 10 seconds on the symbol immediately above it.

 

 

 

 

 

 

  • Your final-number’s symbol is a.  Isn’t it?

How it works:
No matter which 2-digit number you pick, when you add the two digits together and then subtract the total from your original 2-digit number, the result will always be one of the following numbers: 9, 18, 27, 36, 45, 54, 63, 72 or 81.  Because all of these nine numbers have the same symbol, it is a simple matter to display the “correct” symbol… the one associated with the calculated answer.