In this mathematical card trick, the spectator cuts an ordinary pack of cards in two, chooses a card, memorises it and returns it to the pack. They then magically locate their chosen card just by dealing the cards into piles, discarding some along the way until they’re left with only one card – theirs!
Practice cutting the pack so that you’re fairly accurate in getting two equal or near equal halves. Also practice your dialogue well beforehand so that you can run through your instructions to the spectator smoothly.
Give the pack of cards to the spectator and ask them to shuffle them.
You say: “Now cut them exactly in half if you can.”
It might be difficult for them to do this, so after they’ve made the cut you can try and even up the piles by moving a few from one pile to the other, saying that they maybe need a little help to get the cut more exact.
You say: “Take a card from anywhere in either pile, memorise it and place it on top of its pile. Now put the other pile on top so that it’s lost within the deck.”
Next you say: “Now deal the top four cards face down in a row on the table and keep dealing them until you have four piles.”
After the spectator has dealt the four piles, you turn over each pile and spread it out so that all the cards are face up and on view.
Ask the spectator to point to a pile which they think contains their chosen card. You turn that pile face down and discard the other 3 piles.
The remaining pile should contain 13 cards. Ask the spectator to deal this pile into yet another four piles on the table. Note: when this is done the last card dealt should be on the first pile. So ….
You say: “This pile is obviously uneven so we’ll discard it.”
You now have three piles left – each should contain three cards. Note: the middle card of the middle pile is their chosen card.
Ask the spectator to discard the top and bottom cards of each pile. There are now just three cards left.
Pick up these three last cards (from left to right) and give them to the spectator face down. Ask the spectator to again discard the top and bottom card from the pile in their hand.
You say: “Now tell me your chosen card.”
Ask them to turn over and hold up the last card in their hand – it’s their chosen card!