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.