How to Use the 10-20 Force for Magicians

The 10-20 Force is a trick that uses a forced card. A forced card is a card that you already placed in the deck wherever you need it. This trick uses simple math, and with it, you will be able perform a card prediction.

Instructions

Difficulty: Easy

Things You’ll Need:

• Deck of playing cards

1. Using a regular deck of playing cards, memorize the tenth card from the top of the deck. Some people like to place an Ace or a face card, and others think it's more convincing if it appears like any random card. For this article, let's assume we have placed the 5 of hearts tenth from the top.
2. Tell your audience that you are predicting a card that they will choose from the deck. You can simply tell them what your prediction is, or you could write the prediction down on a piece of paper without them seeing and place it in an envelope that you will open at the end of the trick.
3. Make the trick more convincing by using a false shuffle or a false cut in front of your audience. If you choose to do this, though, make sure you are doing it correctly and not changing the location of your force card.
4. Ask the person you are doing the trick for to choose a number between 10 and 20. The number cannot be 10 or 20. It has to be one in between. For example, let's say they choose 17.
5. Count off 17 cards from the top of the deck. Place the first card on the table, the second card on top of the first and so on until you have 17 cards. Now ask your spectator to add the digits of the number they chose, one and seven. They will say eight.
6. Remove eight cards from the top of your 17-card pile in the same way you did in Step 4. The eighth card will be your force card, in this case, the 5 of Hearts.

Tips & Warnings

• Practice the trick using the same force card a few times, using different numbers. It doesn't matter what number between 10 and 20 your spectator chooses, the number you get from adding the two digits will lead you back to the force card.
• There is a slight variation of this trick. You could place your force card ninth from the top of the deck. Then, if the chosen number was 17, your force card would be the next card after you counted eight in Step 6, or the ninth card.