What You Need
A deck of playing cards, a calculator, paper and pencil
Preparation
Put the Ace of Hearts in the eighth position down from the TOP of the deck.
What To Do
Remind your friend that he was free to choose any number from 0-9,999 when he started. Then, after some adding, subtracting, multiplying, and dividing he ended up with another random number. (It will always be 8.) Tell your friend to count that many cards down from the top of the deck, and turn over the LAST CARD. (The Ace of Hearts) Open your prediction and it will match his chosen card!!!
The Mathemagical Secret
Shuffling The Deck
Your friend secretly chooses a card from a deck of cards. When
a magical phrase is spelled out, your friend's secret card mysteriously
appears!
What You Need
What To Do
Finally, hand your friend the deck. As you slowly spell the magical
phrase "h-o-c-u-s p-o-c-u-s a-l-a-c-a-z-a-m", tell her to turn
over one card for each letter. When she turns over the LAST CARD,
it will be her secret card!
The Mathemagical Secret
Your calculator is a remarkable little machine. You've always known
that it can perform mathematical calculations faster and with more accuracy than
most humans, but did you know that it can also talk?
Yes, it's true! Your calculator will talk to you if you push the right buttons. For example, your calculator will tell you its name if you push
clear and then carefully push 353 x 9 + 5,000 - 459 = Just turn your calculator upside down, and it will tell you!
Now that you and BILL have been properly introduced,
it's time to have some fun! Use the calculator alphabet to help you find
the answers to the math jokes and math riddles. If you don't understand
an answer, look at the explanation in the answer section or just ask your calculator!
What You Need
1. What is the only thing that gets larger the more you take away?
What You Need
Preparation
What To Do
Example
The Mathemagical Secret
Other Things To Do
Your friend rolls two dice when you are not looking. After she works a few problems on a calculator, you are able to reveal the two top numbers on the dice!
What You Need
What To Do
The Mathemagical Secret:
1. Your friend enters the number 100
1. (hOLE) hole -- When you take away more dirt, the hole gets larger!
1. Your friend rolls a 2 and a 6.
Tell your friend you are going to predict which card he will choose from the deck of cards. Secretly write ACE OF HEARTS! on a piece of paper, fold it several times, and set it aside until later. Shuffle the cards. (See Below)
Tell your friend to think of a number that is very easy to remember and has 1, 2, 3, or 4 digits.
Examples: His age, lucky number, address, favorite number, etc.
Clear the calculator, hand it to your friend, and have him:
1. Enter his number in the calculator.
2. Multiply that number by 3 and then push the equal sign.
3. Add 24 to that result and then push the equal sign.
4. Multiply that answer by 2 and then push the equal sign.
5. Divide that result by 6 and then push the equal sign.
6. Subtract his original number and then push the equal sign.
Click HERE to see an example.
This trick was written using a kind of mathematics called algebra. Multiplying by 3 and then by 2 is the same as multiplying by 6. Dividing by 6 cancels those operations. Every other operation is mathematical hocus-pocus that eliminates your friend's original number and guarantees the final total will always be 8.
There is a way of shuffling the cards so the Ace of Hearts remains in the eighth position down from the top of the deck. Divide the deck into two piles and riffle the ends together allowing the two piles to interweave. Let the top ten to twelve cards fall last and the Ace of Hearts will remain in the eighth position no matter how many times you shuffle. Practice this many times before trying it with a friend.
Sterling Publishing Company, Inc., New York, NY
Copyright 1991
A deck of playing cards
1. Cut the deck into seven piles and lay them face down on the table.
2. Ask your friend to point to one of the piles. (It doesn't
matter which one she chooses.) Gather together all the piles she did not choose into one pile, and then put her chosen pile on the TOP.
3. Tell her to secretly look at the top card, memorize it, and return
it to the TOP of the deck.
4. Ask her for any number between 20 and 30. (20 and 30 are not
between.)
5. Deal that number of cards into a small pile, one card at a time.
Place the rest of the deck next to the small pile.
6. Ask your friend to find the sum of the digits of her number.
23 ---> 2 + 3 = 5
7. Return that many cards from the small pile to the top of the big pile, one card at a time.
8. Put the small pile on top of the big pile.
Any number between 20 and 30 minus the sum of its digits always equals 18.
"Hocus pocus alacazam" has exactly 18 letters.
Sterling Publishing Company, Inc., New York, NY
Copyright 2001
0 - O, 1 - I, 2 - Z, 3 - E, 4 - h 5 - S, 6 - g, 7 - L, 8 - B, 9 - G
A calculator
25,000 - 68 - 952 - 8,956 - 11,320 =
2. A pet store owner has 19 eels. All but 9 were sold. How many eels does the pet store owner have left?
337.8 x 17 - 9 =
3. Who weighs more, Lee the 5-foot butcher or Bob the 7-foot wrestler?
5 x 7 x 10 - 13 =
4. A barrel of water weighed 75 pounds, but after somebody put something in it, it weighed only 20 pounds.
What was put in the barrel?
500 x 100 + 4,000 - 300 + 4 =
5. What is the largest number that will fit in your calculator's display?
99,999,999 / 9 - 11,058,162 + 656,060 =
6. What did seven do that made all the other numbers afraid of it?
7 x .07 / .7 x 7 + 1.9 =
7. Take two eggs from three eggs and what do you have?
9,992 x .2 x 3 - 2 =
8. How many seconds are in a year?
31,557,600 / 1,000,000 - 26.3476 =
9. How much dirt is in a hole that is 5-feet deep, 2-feet wide and 3-feet long?
5 x 2 x 3 - 30 =
10. Which would you rather have, and old one-hundred-dollar bill or a brand-new one?
100 x 77 + 118.001 - 100 =
Click HERE to check your answers.
Sterling Publishing Company, Inc., New York, NY
Copyright 2002
This number trick is easy to learn and fun to perform for others. You will amaze your family and friends with your supernatural powers when you mysteriously reveal the number that has been secretly chosen!
5 index cards
1. Copy the following numbers on five index cards. Write the numbers exactly as they are shown.
CARD 1
1 3 5 7
9 11 13 15
17 19 21 23
25 27 29 31
CARD 2
2 3 6 7
10 11 14 15
18 19 22 23
26 27 30 31
CARD 3
4 5 6 7
12 13 14 15
20 21 22 23
28
29 30 31
CARD 4
8 9 10 11
12 13 14 15
24 25 26 27
28 29 30 31
CARD 5
16
17 18 19
20 21 22 23
24 25 26 27
28 29 30 31
2. Read the directions below and then practice the trick by yourself. When you have successfully worked the trick two or three times, you are ready to perform it for others.
1. Ask your friend to secretly think of a number from 1 to 31.
2. Give him the 5 index cards and ask him to hand you each card that has his secret number on it.
3. As your friend hands you each card, glance at the number in the top left-hand corner.
4. Mentally add these numbers. Their sum will be his secret number.
5. Finally, hold these cards to your forehead, close your eyes, and pretend the cards are speaking to you as you reveal your friend’s secret number!
Suppose your friend chooses 19 as the secret number. He would hand you each card that has a 19 on it (Card 1, Card 2, & Card 5). The sum of the numbers in the top left-hand corner of each card ( 1 + 2 + 16 ) is 19.
This trick uses the binary number system which is based on the number 2. Look at the number in the top left-hand corner of each card: 1, 2, 4, 8, & 16. Each number has been multiplied by 2 to get the next number. They are called powers of 2. The rest of the numbers on each card have these powers of 2 as parts of their numbers. For example,
look at the card with the 8 in the top left-hand corner. The rest of the numbers on that card have 8 as part of their numbers. 9 = 8 + 1, 10 = 8 + 2, 11 = 8+ 2 + 1, 12 = 8 + 4, etc.
Because the cards are numbered up to 31, you can have someone choose a secret number that is an important date like an anniversary or a birthday.
Sterling Publishing Company, Inc., New York, NY
Copyright 1997
2 dice, A calculator, Paper and pencil
When your back is turned, have a friend:
1. Roll two dice.
2. Multiply the top number on the first die by 5, using a calculator or paper and pencil.
3. Add 12 to that answer.
4. Double that total.
5. Add that result to the top number on the second die.
6. Add 15 to that answer.
Finally, ask your friend for her final total. Just subtract 39 from that total and the top numbers on the dice will magically appear!
Click HERE to see an example.
Multiplying by 5 and then doubling is the same as multiplying by 10. This puts the number on the first die in the tens place. Adding the number on the second die puts that number in the ones place. Every other operation is mathematical hocus pocus and adds an extra 39 to the total. Subtracting 39 reveals the two top numbers on the dice.
Sterling Publishing Company, Inc., New York, NY
Copyright 2002
2. 100 x 3 = 300
3. 300 +24 = 324
4. 324 x 2 = 648
5. 648 /6 = 108
6. 108 - 100 = 8
THE FINAL ANSWER WILL ALWAYS BE 8!
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2. (9EELS) 9 eels -- 9 eels were not sold so there are 9 eels left!
3. (LEE) Lee -- Lee the butcher weighs meat all day long so he weighs more!
4. (hOLES) Holes -- 55 pounds of water leaked out!
5. (GOOGOL) googol -- A googol is a 1 followed by 100 zeroes so it has 101 digits!
6. (8,9) -- 7 (seven) 8 (ate) 9 (nine)!
7. (2 EGGS) 2 eggs. You took 2 eggs so you have 2 eggs!
8. (12S) 12 seconds -- January 2, February 2, March 2, etc.!
9. (0) 0 -- No matter how you turn the calculator, there is no dirt in a hole!
10. (100-BILL) $100 bill. It is worth $99 more than the new one($1)!
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2. 2 x 5 = 10.
3. 10 + 12 = 22
4. 22 x 2= 44
5. 44 + 6 = 50
6. 50 + 15 = 65
65 - 39 = 2 6. The number on the top of the first die is 2, and the number on the top of the second die is 6!
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