well, its by elminination. you just create all but the last few cards so that when it gives you a number to advance, no matter what number you originally started with, you will eventually wind up on the same number. say you choose 8, and on the eigth turned card it shows a 3, then another number until you get to the last card... say the number 4. Now, lets say on the SAME game you choose the number 6. You count starting from the sixth card and its number is 2, and so on until the numbers it tells you to cout with land you also on the final number 6. So, of course you're new number for it to guess is six. It's not guessing your original number, but instead tricking you into thinking you have control over the situation when actually it forces you, by using certain numbers on the first 10 and then calculating what numbers to use afterwards to reach its final destination. They will ALL end up on the same last card. Here is an example. I choose 6. The sixth card turned says 4. So I look at the 10th card (6+4) and its number is 2. So the 12th card is my next one. It's number is 7. So now lets say the 17th card is the last one and its number is 4. Now lets say that instead I choose the number 3. The 3rd card's number is 8. So, my next card to look at is 11 (8+3). On the 11th card the number is 2. So now to the 13th card. It's number is 1. So the next, or 14th card. Its number is 3. Well, I am now on the 17th card. Pretend there are 20 cards and the 17th card number is 4. Well, there is no card number 21, so the last card used is the 17th card. As you see, both numbers choosen at the beginning (and actually, no matter what number you choose at the beginning) wound up on the same card number. Its just a play with math.
