a friend of mine knows this trick, he's some kind of a comedian, he does it sooooo funny. i saw him showing it to a few people, and he got some amazing responses!!! after the person says the group he's card is at, he just asid, i know that, just wanted to c if u were paying attantion!!! after he says that, he puts he's hand over the 3 piles, he says he's getting energies from the cards, after like 10 sec, he pick them up and do the order again. i always lmao when he does that trick, this only proved to me that any trick can get great responses, it only dependse in the way that u present the trick

Tomer

from reading that i just figured out the invisible deck lol but that's ok i'm too busy using brainwave deck to make my own invisible deck

oh what ever you just said that cause I said ," I hope I didn't reveal anything!"

lol so i was in the common room playing pool one day and a girl just walks in and says to someone do u wanna see a card trick, they say yeah, she does this 21 card trick and she was like WOOOOOOOOOW OMG OMG OMG!!! UR SUCH A GREAT MAGICIAN and i was stood there laughing at the situation to myself, but what really peed me off was when the girl who had it performed on her came back later, she had a whole CROWD of people following her JUST to see this magic trick and it was annoying cos it was bigger than any crowd i ever got
i was tempted to jump in and perform triumph or sumthing but nah, pool was more important

lol so anyway, whats the maths principle behind this trick? i cant work out how it works

You should really work on getting some help for that.

I laughed out loud at this topic because it has happened to me so many times.

I finish a few tricks that astonish the spectators and all of the sudden some guy says, "I know a trick!"

Sure enough he puts 7 cards in each of the 3 rows and I pretend like I am interested.

Man I am glad I am not the only one!

happened to me a few nights ago.. the guy calls it his psychic trick... i actually did this trick when i was little with 3 piles of 5 cards... i thought i was houdini...

Well, you put the long column with the selection in to the middle of the three columns when you pick the cards up. This puts the selection somewhere in the center of the twenty-one cards--between 8-14.

So, when you set the card down again the selection will fall somewhere in either the 3rd through the fifth three-card row. When they point to the column again, you have now narrowed the selection to one of three cards (or two). When you repeat the steps, the selection will always be one of the three cards in the middle row.

Not sure that this is really "math", but it is the principal. I think they are called "math" tricks, when any spectator, can take any deck and exactly repeat your steps, without any set up, and end up doing the same trick.

I think this is opposed to self-working tricks, which, although not requiring any slights, do require some secret set up to work.

Hmm..I thought the 27-card trick was similar to the 21-card one but apparently they're somewhat different.

For the 27-card trick and have the spectator select a card from one of the 27 and a number from 1-27 and have him/her tell you the number.

Deal the cards into 3 colums of 9, left to right, ask the spectator to indicate the column the chosen card is in, and collect back the cards. This step is repeated three times with the way the cards are collected back being as follows:

1st time: Divide the spectator's number by 3. If the remainder is 1, the column with the selected card goes on top of the pack (pack face down), if it is 2, it goes in the middle, and for 3, on the bottom.

2nd time: Add the digits of the chosen number. If the result is 1-3, column with the selected card goes on top of the pack, 4-6, in the middle and for 7-9, on the bottom. (There is one special case here if the chosen number is 19, it goes on top: 1+9=10, then 1+0=1)

3rd time: If the chosen number if from 1-9, column with the selected card goes on top of the pack, 10-18, the middle and 19-27, on the bottom.

When the cards are collected for the final time, the chosen card should be at the position of the chosen number and you can reveal it however you wish.

I'm not sure how this actually works but it does!

Hey, I do that trick! Not in shows, I mean, but if someone gives me a deck of cards I'll do the 2 card monte and that trick. It gets good reactions. Do a pass or something to get the card to the bottom and then let them hold the deck and slap it from their hands. For some scientific reason the bottom card stays in their hands. Sorry, I don't kno the tricks name.

Hey, I do that trick! Not in shows, I mean, but if someone gives me a deck of cards I'll do the 2 card monte and that trick. It gets good reactions. Do a pass or something to get the card to the bottom and then let them hold the deck and slap it from their hands. For some scientific reason the bottom card stays in their hands. Sorry, I don't kno the tricks name.

Im not even sure that this is good enough to be called a trick. Like someone said, its just a maths formula.

You can even do the 16 card trick where you lay our four rows of four cards. DUMB

It often happens that someone wants to show me a card trick. Invariably the 21 card trick. As with all long card tricks (this trick especially), I find the experiance to be extremely painfull. I exercise control and praise the performer on his accomplishment. It does wonders for my immage. The other alternative would be more fun. (See prop grabber)

If you want to see the principle of how this trick works, do as follows.

Deal out the standard three rows of seven.

Say you pick a card in the middle row: Just throw out the other two rows (this is basically what you are doing, since you know that the card is in the middle row now).

Now deal out the cards in three rows once again, but only with the pack of cards from the middle row.

See what row your card is in, and throw out the others. (Say that it is once again in the middle).

Now take the pack of 2-3 cards, and deal them out again. Name which "row" your card is in. So basically only one card can have the exact order as the chosen card, so you narrow it down to one card, by process of elimination. This is all disguised by keeping all three piles, instead of doing the trick as explained above, which makes the trick painfully obvious.