The missing card. Effective trick and its solution

EFFECTIVE FOCUSES AND THEIR CLUES
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The missing card. Focus Secret

Spectacular tricks and their clues

Directory / Spectacular tricks and their clues

Focus Description:

While the demonstrator is standing with his back to the audience, one of them takes a card from the deck, puts it in his pocket and shuffles the deck. The showman then turns, picks up the deck, and begins laying out the cards one at a time, face up. After all the cards come out, he names the missing one.

Focus secret:

The numerical value of the missing card can be determined by calculating in your mind the sum of the numerical values of the cards laid out on the table. At the same time, jacks are assigned the value 11, ladies 12. Kings can be considered zeros and not taken into account at all.

Without kings, the sum of the numerical values of all cards in the full deck is 312. Therefore, to find the numerical value of the missing card, you need to subtract the sum of the numerical values of 312 cards from 51. If this last sum turns out to be 312, then the missing card is the king.

When showing this trick, it is important to master the methods of quick counting. So, for example, it is obvious that when adding 11, it is convenient to first add 10, and then another one, and to add 12, you first add 10, and then two.

A further increase in the speed of counting can be achieved by "discarding the twenties", i.e. counting modulo 20. In other words, as soon as the sum exceeds 20, discard this number and keep only the remainder in memory. After the last card is laid, you will have to memorize a small number from 0 to 12 inclusive. Subtract this number from 12 and you get the numerical value of the missing card.

If the last sum is 12, then the missing card is the king. It seems to us that the elimination of "twenties" is the best way to speed up the count. However, many people prefer to discard 13 in this case. Then, for example, adding 7 and 8 and discarding 13, you memorize 2. Instead of adding 11 (in the case of a jack) and then discarding 13, it is easier to subtract 2 without adding anything. In the case of a queen, discard 1. It is clear that kings do not need to be taken into account.

When you have finished counting, subtract the last digit from 13 and you will get the numerical value of the hidden card. After it is found, you can, of course, by handing over the cards a second time, find out the suit of the missing card. However, the secret of the focus is immediately revealed. How to determine the suit of the card at the first layout, simultaneously with its numerical value?

One way - really difficult if you do not have the technique of quick counting in your mind - is to simultaneously memorize the total number for the suit and the same number for the numerical value of the card. Let's assign, for example, to the cards of the spade suit the numerical value 1, the clubs - 2, the hearts - 3, the diamonds - zero (and we do not take them into account). When adding, tens are discarded, and as a result one of four numbers is obtained: 5, 6, 7 or 8. Subtracting it from eight, you will find the suit of the hidden card.

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