Often while solving a mathematical problem one is stuck, but somebody else solves the same problem easily via a different method, formula or trick. This is one of the reasons that many people call Mathematics as MATH-MAGIC. Although there is no such word in the dictionary, but when it comes to the game of cards you will always come across a trick that is known as Math-Magic Card trick. In this trick, a spectator selects a card out of three columns and later goes through a number of steps that help him find his card from the piles of cards facing down.
Make three columns dealing cards in a horizontal row such that there are seven cards in each column. With the cards facing upwards, ask a spectator to mentally choose a card from those columns and not tell you.
Repeat the same procedure of dealing the cards in three piles. This time the spectator’s card will be located at the 11th position as you count from the top.
Now remove three cards from the deck and place their group on a table. Make two more groups on the right of the first one so there are two rows of three piles, while you place the last pile of three cards under the middle column.
After you make seven piles, tell the spectator to touch any three out of them. If the piles touched include the pile at the far left of the second horizontal column ("X Pile"), then lift the other four piles and place them aside, or lift the other three and put them aside.
Keeping in mind where the pile at far left of the second horizontal column ("X Pile") ends up, rearrange the remaining piles and ask the spectator to touch any two piles.
While you keep on removing piles according to the spectator's choices, make sure that you do not remove "X Pile" unless only that one is left.
When you are only left with "X" Pile", ask the spectator to choose TWO out of the THREE cards that you spread out.