Let’s verify: After round 1, their card is in positions 10-18. After round 2 (again middle pile), it narrows to a set of 3 positions. After round 3, it collapses to exactly one position—the 14th card.
"Now deal them into three piles, one by one. Left, middle, right, left, middle, right..." How To Do The 27 Card Trick
: Ask the spectator to point to the pile containing their card. Let’s verify: After round 1, their card is
The magician removes 27 cards from the deck and spreads them face-up on the table, showing they are random. They are then shuffled thoroughly. The magician hands the deck to a spectator and asks them to peek at one card and remember it. The spectator does so. "Now deal them into three piles, one by one
When you ask a spectator to identify which pile their card is in, you are essentially asking them to give you a single piece of data: "Where is the card?" In a set of 27 cards, you need exactly three bits of information to locate one specific card. By dealing the cards out three times, you are narrowing the location of the card from 27 possibilities down to 1.
