Have a student pick a card from the deck of cards. Have them show the entire class the card. Also have the following chart on the board for students to refer to:
Card Numbers Value of Suits
Ace=1 Clubs=1
2=2 Diamonds=2
3=3 Hearts=3
… Spades=4
10=10
Jack=11
Queen=12
King=13
Have the students:
1. Take the card number
2. Add the number that is one more than this number. For example, if the card was a 2, add 2+3.
3. Multiply that result by 5.
4. Add the value of the suit to that answer. (Hearts=3)
5. Add 637 to that result and have them tell you the number.In your head you now subtract 642. Looking at the final result you can figure out what card the kids started with. The tens digit corresponds to the number of the card and the ones digit is the suit number. For example, if the final value was 73, the card was a seven of hearts. If the number was 121, the card was a queen of clubs! Try this several times depending on time, and then let students know that you are subtracting another number and show them how to read the results.
It is a more complex algebraic expression, and instead of working through it, it could be suggested as a challenge problem for those who want to try it at home.
Direction How the Algebraic
Number Changes Expression
Take the card number 7 x
Add the number that is 15 x+x+1= 2x+1
one more than this number
Multiply that result by 5 75 10x+5
Add the value of the suit 78 10x+y+5
to that answer
Add 637 to that result 715 10x+y+642
Subtract 642 73 10x+y
Since you will always end up with 10 times the card number plus the suit value, you can read off the answer by looking at the tens unit and ones unit separately to figure out any card in the deck!
7. Predict a pair
Pre-arrangement : Remove all tens and picture cards from the deck.
The magician asks a spectator to shuffle the cards. He then takes a bunch of cards and fans them in front of the spectator who is asked to pick a card from the fan. The spectator is to remember the chosen card and replace it in the pack.
The magician then asks the spectator to multiply the value of the card he picked by 2 and then after adding 5, to multiply that number by 5. The spectator is then asked to remember the total he arrives at.
Next, the magician lets the helper select another card in the deck, and that value, he is to add to the total that he had arrived at earlier. The spectator is finally asked to reveal his total to the magician.
How the Trick is Done
When you hear his total, subtract 25 ….. The two digits you get will be the two cards he chose.
Example: if his total is 86 then the third two selected cards would have been an 8 and a six.
This is a self-working mathematical trick.
8. As Many As You
This mathematical trick can be performed with any pack
Effect: The magician can reveal the exact number of cards taken by a spectator.
Method: The magician asks a spectator to take a few cards from the top of the pack but to conceal them from the magician to the extent that the neither the performer nor the spectator can tell how many were taken.
The magician then also takes a bunch of cards secretly making sure he takes more than the spectator.
Next, the magician asks the spectator to turn his back and count his cards silently so as to give no clue to the performer.
The magician counts his own at the same time then in a novel albeit roundabout way reveals the exact number of cards held by the spectator.
How the Trick is Done
When the magician counts his cards—say for example he has 17 cards. He takes 3 from the total making a new total of 14; then he says to the spectator: “I’ve got as many as you….3 more …..and enough to make your number up to 14”. He then asks the spectator to reveal how many cards he is holding and the prediction is proven true as the magician first deals out the number of cards to match the spectators total (in this case 10)—then three more—then enough to make the spectators total up to 14. (the magician deals his remaining 4 cards).
This will work whatever number the spectator or magician is holding.
Another example: if the magician’s total 20 then he would say: “I’ve got as many as you….3 more …..and enough to make your number up to 17”. He would then ask the spectator how many cards he is holding and on hearing “8” the magician would first deal out the number of cards to match the spectator’s total (in this case 8—then three more—then enough to make the spectators total up to 17. (the magician deals his remaining 9 cards).
This is a self-working mathematical trick.
9. Piano Duets
This mathematical trick uses the metaphor of playing the piano to colourful effect.
Method: The magician invites a volunteer to sit at his table and to place his hands as if playing the piano.
He then places two cards between the third and little finger of the volunteer’s left hand saying: ‘Here’s one pair’. Then another two cards between the third and second fingers saying:’ Here’s another pair’. Next the magician puts two cards between the first and second fingers saying: ‘And here’s another pair’. Lastly, he places two cards between the volunteer’s forefinger and thumb saying: ‘And yet another pair here as well’.
The magician does the same with the volunteer’s right hand except this time he puts only one card between the thumb and forefinger stressing: ‘But this one is an odd card’.
The performer repeats what he has done always stressing that cards were placed in pairs. He then continues in the same fashion. Only this time, he removes each of the pairs of cards from the volunteer’s left hand, separates them and places them side by side on the table—again stressing: ‘Here’s a pair’. He continues with the helper’s right hand pairs until he reaches the one odd card which he hands to the volunteer asking him to place it on top of either of the two piles.
This done, the magician taps the pile on which the volunteer placed the odd card and says that the odd card will magically fly across to the other pile. He then picks up the pile which is supposed to have the extra card added and separates the cards into side by side pairs saying each time once again: ‘Here’s a pair’.
The volunteer sees that there are four pairs of cards and the odd card has apparently vanished! The magician separates the other pile in the same manner and the volunteer sees that there is an odd card!—the illusion is complete—the odd card must have jumped across to the other pile!
How the Trick is Done
This trick works because of course earlier in the trick the volunteer is holding 4 pairs of cards in the left hand and 3 pairs and one odd card in the right. The cards are then divided into two piles of seven cards which the volunteer doesn’t notice because of the emphasis on pairs. When the odd card is added to a pile, it turns it into an even numbered pile!
10. Mental Agility
This mathematical trick can be performed with any pack.
Effect: The magician can reveal a chosen card even when it is selected with his back turned.
Method: Get a spectator to think of a number between one and 10. Then ask him to shuffle the pack (this can be be his own if you like) and get him to count down to the number thought of and make a note of the card but to leave it in the same position. Get him to do this while your back is turned.
After he has done this, turn around and take the pack placing it behind your back then rapidly count off 19 cards and as you do so reverse their order replacing them on the top of the pack. As you do this, say that you will put the card at number 20.
Finally, bring the pack from behind your back and ask the spectator which number he thought of. For example, if it was a five then begin your count with (in this example) 6 dealing the cards one at a time. When you reach 20, get the spectator to name his card and when you turn it over, to his amazement, it is his card.
How the Trick is Done
This is a self-working mathematical trick.
11. Mental Agility Plus 1
This mathematical trick can be performed with any pack.
Effect: The magician can reveal a chosen card even when it is selected with his back turned.
Method: While your back is turned, get a spectator to shuffle a pack of cards which can be his own if you like, then to select a card from the pack and place it face down on the table. Next, ask the spectator to make two small piles of cards each with the same even number next to his selected card (for example, two piles of four cards or two piles of five cards) and to place one of the piles in his pocket and the other one on top of the selected card which is face down on the table. Finally, ask the spectator to take the pile of cards on the table including his selected card and place the pile on top of the pack. After all this is done, you can turn around.
Now you, the magician pick up the pack and put it behind your back reminding the spectator how you couldn’t possibly know which card he selected and its position in the pack. Next, count 15 cards from the top reversing their order as you do so and replace them on top of the pack. Bring the pack round the front until the spectator that you are now going to make the situation even more difficult for yourself by asking him to take the small packet of cards from his pocket and place them on top of the pack as well. Get the spectator to do this and when it is done, the selected card will now be the 15th card from the top of the pack and of course there are many ways that you can reveal this in as entertaining way as possible.
How the Trick is Done
This is a self-working mathematical trick. In fact, you could have reversed any number of cards on top of the pack but whichever number it must, it is always the higher than the number contained in each of the piles of the spectator’s dealt cards.
12. Count On Me
This mathematical trick can be performed with any pack.
Effect: The magician can reveal a chosen card even when it is selected with his back turned.
Method: Ask a spectator to shuffle his own pack of cards and count off any number of cards as long as it is less than 15. If, for example, he chooses number five then he looks at the fifth card, remembers it and then he must replace the cards in the same order.
While he is doing this your back is turned to him; then turn around and take the pack placing it behind your back and count off 15 cards from the top putting them on the bottom but you must be careful not to reverse their order when you count them. At this point, you can make it look as if you are fumbling around and unable to find a card. Next, hand the pack back to the spectator and tell him to transfer from the top to the bottom of the pack the same number of cards that he counted at first but before he does this he is to check that his card is not anywhere near this position.
After he has done this, take the pack once again, put it behind your back and transfer 15 cards from the bottom of the pack to the top. The bottom card will now be the card the spectator noted. Reveal the selected card in as mystifying way as possible but, in fact, the spectator will not realise that he has in effect performed the trick himself.
How the Trick is Done
This is a self-working mathematical trick.
13. The Name Of The Card Is…
You secretly predict which card will be chosen. Then you ask a friend to select a number randomly and count down that many cards in the deck. At first this card doesn’t match your prediction, but after a few comical adjustments, the name of the card mysteriously appears!
Things you need
A deck of playing cards
A calculator
Paper and pencil
Preparing the trick
Put the 10 of Hearts in the eighteenth position down from the top of the deck.
The Secret
Announce that you are going to predict which card will be chosen from the deck. On a piece of paper, write: THE NAME OF THE CARD IS. Fold the paper so that your friend may not see what you’ve written and put it aside until later. Ask your friend to:
1. Enter a 3-digit number into the calculator. (The first digit must be larger than the last digit.) Example: 845
2. Reverse this number and subtract it from the first number. -548 3.
Add the digits in the answer. 297 2+9+7=18 The digits will always add up to 18!
Tell him to count down that many cards in the deck. It will be the 10 of Hearts.
Finally, ask him to open the piece of paper and read your prediction.
He’ll read, “THE NAME OF THE CARD IS”.
Say that you were in such a hurry that you forgot to finish your prediction. Then make these adjustments and his card will mysteriously appear!
-cross off the H in THE
-cross off the AME in NAME
-cross off the T in THE
-cross off the CD in CARD
-change the I in IS to a T by crossing the top
leaving THE TEN OF HEARTS
14. Number Magic Mathematical Trick
Materials Needed:
1. 1 Standard Card Deck with all Tens, Jacks , Queens, and Kings removed.
2. Ability to do maths in your head.
3. Pad of paper and pencil.
How the Trick Appears:
Using maths you figure out two cards that a person has chosen.
How the Trick Works:
Have someone shuffle the cards. Take a group of cards and hold them in your hand, spread out in the shape of a fan. Ask him/her to choose a card from among them. Tell the person to remember it and then to put it back in the deck.
Give the person a piece of paper and pencil if his not that good at doing maths in his head, or remembering a few numbers at a time.
Ask him to double the value of the card he picked, and then to add 5.
Now have him multiply that number by 5. Tell him to remember this number.
Instruct him to look at another card in the deck, and to add its value to the total that he had computed before. He is to tell you the final total of everything.
In your head, subtract 25 from the total. The two digits you get are the same as the two cards he chose.
Example: he choose a Six (6), then a Three (3).
6 (doubled) = 12 plus 5 = 17. Multiply times 5 = 85.
Three added to total = 88. You subtract 25 = 63.
They picked a Six and a Three!
Notes: Aces are counted as “1”
Practise this trick before performing. It’s easy to get confused on how a card trick works just from reading about it.
Having a deck of cards in your hands as you try and learn the tricks on this page will make it much easy to learn, understand and then master.
