Always Five (5)

Find a calculator or a pencil and paper. Ask your friend (or everyone in the room) to choose any number.

Example :43

Add the next highest number to it

43 + 44 = 87

Add 9

87 + 9 = 96

Divide by 2

96 / 2 = 48

Subtract your original number

48 - 43 = 5

Everyone's answer will always be 5 Try another number.

More Always Five

Choose any number between 1 and 99

Example :22

Multiply this number by 5

22 x 5 = 110

Add 25 to your product

110 + 25 = 135

Divide this number by 5

135 / 5 = 27

Subtract your original number

27 - 22 = 5

Everyone's answer will always be 5

One More Trick

Choose any number.

Double it.

Add 10 to it.

Now half the number.

Then subtract your first number.

The answer will be five.

Math Magic/Tricks

Math Magic/Tricks

Trick 1: Number below 10

Step1: Think of a number below 10.

Step2: Double the number you have thought.

Step3:Add 6 with the getting result.

Step4: Half the answer, that is divide it by 2.

Step5: Take away the number you have thought from the answer, that is, subtract the answer from the number you have thought.

Answer: 3

Trick 2: Any Number

Step1: Think of any number.

Step2: Subtract the number you have thought with 1.

Step3: Multiply the result with 3.

Step4: Add 12 with the result.

Step5: Divide the answer by 3.

Step6: Add 5 with the answer.

Step7: Take away the number you have thought from the answer, that is, subtract the answer from the number you have thought.

Answer: 8

Trick 3: Any Number

Step1: Think of any number.

Step2: Multiply the number you have thought with 3.

Step3: Add 45 with the result.

Step4: Double the result.

Step5: Divide the answer by 6.

Step6: Take away the number you have thought from the answer, that is, subtract the answer from the number you have thought.

Answer: 15

Trick 4: Same 3 Digit Number

Step1: Think of any 3 digit number, but each of the digits must be the same as. Ex: 333, 666.

Step2: Add up the digits.

Step3: Divide the 3 digit number with the digits added up.

Answer: 37

Trick 5: 2 Single Digit Numbers

Step1: Think of 2 single digit numbers.

Step2: Take any one of the number among them and double it.

Step3: Add 5 with the result.

Step4: Multiply the result with 5.

Step5: Add the second number to the answer.

Step6: Subtract the answer with 4.

Step7: Subtract the answer again with 21.

Answer: 2 Single Digit Numbers.

Trick 6: 1, 2, 4, 5, 7, 8

Step1: Choose a number from 1 to 6.

Step2: Multiply the number with 9.

Step3: Multiply the result with 111.

Step4: Multiply the result by 1001.

Step5: Divide the answer by 7.

Answer: All the above numbers will be present.

Trick 7: 1089

Step1: Think of a 3 digit number.

Step2: Arrange the number in descending order.

Step3: Reverse the number and subtract it with the result.

Step4: Remember it and reverse the answer mentally.

Step5: Add it with the result, you have got.

Answer: 1089

Trick 8: x7x11x13

Step1: Think of a 3 digit number.

Step2: Multiply it with x7x11x13.Ex: Number: 456,

Answer: 456456

Trick 9: x3x7x13x37

Step1: Think of a 2 digit number.

Step2: Multiply it with x3x7x13x37. Ex: Number: 45,

Answer: 454545

Trick 10: 9091

Step1: Think of a 5 digit number.

Step2: Multiply it with 11.

Step3: Multiply it with 9091. Ex: Number: 12345,

Answer:1234512345

Card Trick =_4

Walk around the classroom and have students pick one card each from the deck. Ask them to be sure that no one sees their card.

Have them perform the following mathematical operations:

1. Write the face value of the card that you selected on a piece of paper.

The aces and face cards have the following values:

Ace = 1, J = 11, Q = 12 K = 13.

2. Double the face value.

3. Add 3.

4. Multiply by 5.

5. If the card you selected is a club, add 1; a heart, add 3;

a diamond, add 2; or a spade, add 4.

6. Now tell me your answer and I will show you the card that you selected.

For the most dramatic results, have an oversized deck of cards (7" x 4.5"), ordered by suit and value, for yourself. After completing the mental calculations listed below, you instantly determine the card any student selected and then pull it out of your deck.

By mentally subtracting 15 from the final answer your student gives you, your two or three digit answer tells you the face value and the suit of the card.

The digit(s) in the tens and hundreds place(s) tells you the face value of the card; you will have a number in the hundreds place only when the card's face value is a ten, or a face card.

The ones digit tells you the suit of the card. A one in the ones place means that the suit of the card is a club, a two indicates a diamond, a three indicates a heart, and a four indicates a spade.

I order my demonstartion deck with the clubs on top, then diamonds, then hearts, then spades -- Then I don't have to memorize how the suits were ordered.

Why does this work?

1.Write the face value of the card that you selected on a piece of paper.

Let c = value of the face card.

2. Double the face value.

Then you get 2c.

3. Add 3.

Then you get 2c + 3.

4. Multiply by 5. Then you get 10c + 15.

5. If the card you selected is a club, add 1; a heart, add 3;

a diamond, add 2; or a spade, add 4.

Let s = suit, so you now have 10c + 15 + s.

6.Now tell me your answer and I will show you the card that you selected.

Subtract 15 to get 10c + s.

The face value is in the tens place and the suit is in the units place.

Card trick =_3

Vikas MyAiM proposed the following problem:

Say you are sitting in a dark room, where you are handed a deck of 52 cards. Ten of those cards have been turned facing up; the rest are facing down. Your job is to separate the cards into two stacks, each containing the same number of cards facing up.

Is it possible to do this? Marilyn vos Savant answered the question: "Yes, just deal yourself 10 cards and turn all of them over! Try it and see, readers."

Mike Ecker explains: Say that N of the 10 cards that make up the second pile are already facing up before you turn the pile over. Then the other 10-N cards in this same pile are face down. Moreover, the first pile still has 10-N cards face up.

By now reversing the 10 cards you have dealt yourself, instead of N up and 10-N down, you now have 10-N face up -- matching the 10-N face up in the first pile. Very clever and totally independent of where the 10 cards lie!

Card trick =_2

Jim Steinmeyer is one of the nation's most creative inventors of magic tricks. A few years ago he invented a marvelous mathematical trick. Known as the Steinmeyer nine-card trick, it has since been given many clever means of doing it by other magicians.

Here is one of the simplest:

Take any nine cards from a standard 52-card deck and deal the nine cards into three piles of cards each. Pick up any pile and remember its bottom card. Drop this pile on top of one of the others, and these six on top of the last pile. The cards remain down throughout.

Hold the nine cards down and spell the value of the chosen card by dealing one card down to the table for each letter. So, if the card chosen is the Queen of Spades, spell Q U E E N and drop the remaining cards on top.

Pick up the packet and spell O F. As before, drop the rest of the cards on top. Pick up the packet and spell the suit of the card you selected: S P A D E S. Drop the rest of the packet on top.

The position of the chosen card should now be at a random spot because card names spell out with as few as 10 letters up to as many as 15. So, now spell M A G I C and turn over this last card. Believe it or not, this will always be the selected card!

Card trick =_1

Take a deck of cards facing up and count off from whatever the first card is until you say "king." (for example, if a seven is the top card, you would say 7-8-9-10-J-Q-K).

Take these cards and lay them face down and start over with another stack

(In the example above, make certain that the 7 is on top).

Do this until all the cards (52) are used up.

If there are any left (where you could not count to King), hold these in your hand.

Then pick up all but 3 stacks and add those cards to the ones that are in your hand.

Now with the three stacks facedown on the table turn the over top card on two of the stacks.

Add the face value of those two cards together. (J=11 Q=12 K=13)

Count off this total from the cards you are holding.

Then count off 10 more.

The total of cards left in your hand is the exact same as the top card on the third stack.

Your age by eating out!

Don't tell me your age; you probably would tell a falsehood anyway -- but your waiter may know!

Here's how to find your age using some Dining and Restaurant Math!

1. First of all, pick the number of times a week that you would like to go out to eat. (more than once but less than 10)

2. Multiply this number by 2 (just to be bold)

3. Add 5

4. Multiply it by 50

5. If you have already had your birthday this year add 1757 .... If you haven't, add 1756.

6. If the current year is not 2007, you must add one for each year past 2007.

7. Now subtract the four digit year that you were born.

You should have a three digit number

The first digit of this was your original number

(i.e., how many times you want to go out to restaurants in a week.)

The next two digits are

YOUR AGE! (Oh, yes, it is!)

Twenty Objects Trick

1. Place 20 objects on the overhead.

2. Have a student remove any number of items from 1 to 10.

3. The items that remain will be a two-digit number.

4. Have a student find the sum of these two digits and remove that many more items from the projector.

5. Have a student give you some of the remaining objects.

6. You should subtract that number from 9 and tell her how many objects she has in her hand.

Why does this work?

After removing 1 to 10 items from the 20 objects you started with, you will have a number from 10 to 19.

When you add the 2 digits together and subtract from the number 10 to 19, you will always get 9.

So, when your student gives you some of the items remaining, you need only to subtract from 9 to find how many items she has.

The Dictionary Trick

This is my favorite trick. A student of mine from Herndon High School in Fairfax County, Virginia showed this to me in the late 1960s, and I used it nearly every year after that until I retired in 2006.Ask a student to pick a three digit number (where the first and last digits are different).

Then have the student reverse the digits and subtract the two numbers.

Give the student a dictionary, and have her look up the fifth word on the page corresponding to her last calculation. There are only nine words in the dictionary that your student could have chosen.

It is at this point that you will need a clue. Ask the student to give you the first letter of the word.

Now, go to the page number in the following list which has words beginning with the letter the student told you: page 99, page 198, page 297, page 396, page 495, page 594, page 693, page 792, or page 891.

Count down to the fifth word on that page and you have found the word.

It is more impressive if you memorize the nine words on the above pages.

When I showed this trick to Ray Frantz, an English teacher at Handley High School, he added another feature to the trick. One of us would bring his class down to the other teacher's room. I would go outside the room and a student would volunteer to go with me and make sure that I wasn't listening to what was going on in the room. Then the students would choose the number and select the word. Then I would come back in the room and guess the word.

Since Mr. Frantz was in the room when the word was chosen, and the only clue I needed was the initial letter of the word, he would "send me the clue" by making a statement when I reentered the room. The first letter of the third word would be the letter that I needed to know. For example, he would say, "Mr. Pleacher, come in and show us how this is done" when the word started with a c; or he would say, "The students don't believe that you can do this" when the word started with a d.

Remember that you can only use this trick a few times before it starts to repeat, since there are only nine pages that the word will fall on.

Why does this work?

The difference between the original three-digit number and the number with its digits reversed is always a multiple of nine -- in fact, the middle digit must be a nine (you must always borrow in doing the subtraction) and the sum of the digits is always eighteen.

So, the only possible answers after the student has done the subtraction are: 99, 198, 297, 396, 495, 594, 693, 792, and 891.

As long as you don't choose an unabridged dictionary, each of the page numbers above will be found under a different letter.

Phone Number Trick

1. Get a calculator. (You won't be able to do this one in your head)

2. Key in the first three digits of your phone number (NOT the area code)

3. Multiply by 80

4. Add 1

5. Multiply by 250

6. Add the last 4 digits of your phone number

7. Add the last 4 digits of your phone number again.

8. Subtract 250

9. Divide number by 2

Do you recognize the answer?

Explanation:

Let x= 1st three digits of phone number

let y= last 4 digits of phone number

x

80x

80x + 1

250(80x + 1) = 20000x + 250

20000x + 250 + y

20000x + 250 + 2y

20000x + 2y

10000x + y

This last step shows why you get your phone number back. x (which represents your first three digits of your phone number) is multiplied by 10000, which just moves it over 4 places and then y is put in the four places on the right.

PERCENTAGE COMPUTATION

Calculate 65% of 460:

50% of 460 = 230

10% of 460 = 46

5% of 460 = 23 (half 46)

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65% of 460 = 299 (sum)

EXAMPLE.

Calculate 67.5% of 460:

50% of 460 = 230

10% of 460 = 46

5% of 460 = 23 (half 46)

2.5% of 460 =11.5 (half 23)

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67.5% of 460 = 310.5 (sum )

MULTIPLICATION OF 11 WITH ANY NUMBER OF 3 DIGITS.

Let me explain this rule by taking examples

1. 352*11 = 3---(3+5)---(5+2)---2 = 3872 Means insert the sum of first and second digits, then sum of second and third digits between the two terminal digits of the number

2. 213*11 = 2---(2+1)---(1+3)---3 = 2343

EXAMPLE-:

Here an extra case arises

Consider the following examples for that

1) 329*11 = 3--- (3+2) +1--- (2+9-10) ---9 = 3619 Means, if sum of two digits of the number is greater than 10, then add 1 to previous digit and subtract 10 to the associated digit.

2) 758*11 = 7+1---(7+5-10)+1---(5+8-10)---8 = 8338

LEARN MATH MAGIC AND MAKE FOOL YOUR FRIENDS

Trick 1: Step1:Think of a number . Step2:Multiply it by 3. Step3:Add 6 with the getting result. Step4:divide it by 3. Step5:Subtract it from the first number used. Answer:2 Trick 2: Any Number Step1:Think of any number. Step 2: double the number. Step3:Add 9 with result. Step4:sub 3 with the result. Step5:divide the result by 2 .Step6:Subtract the number with the number with first number started with. Answer: 3 Trick 3: Any three digit Number Step1:Add 7 to it. Step2:Multiply the number with 2. Step3:subtract 4 with the result. Step4: Divide the result by 2. Step5:Subtract it from the number started with. Answer: 5

Finding Someone’s Age - Number Trick

*.Ask the person to multiply the firstnumber of his or her age by 5. .Tell them to add 3..Now tell them to double this figure.*.Finally, have the person add the second number of his or her age to the figure and ave them tell you their answer.*.Deduct 6 and you will have their age

Grey Elephants in Denmark - Number Trick

.Pick a number between 1 & 10..Multiply by 9.*.If the result is a two digit number, add the two digits together.*.Subtract 5 from the resulting number.*.Beginning with the letter A as 1, count over in the Alphabet that many letters (I usually will count a few out loud " A is 1, B is 2, C is 3.")*. Now think of a Country that beginswith your letter (Only big Baseball fans, or Cigar smokers will get the Dominican Republic, the rest will get Denmark)*.Take the second letter in your county and think of a Circus Animal that begins with that letter.*.Wait a couple of seconds and say"There are no Elephants in Denmark!"Explanation:The result of step 3 (adding together the digits of a multiple of nine) will always yield"9", so subtracting 5 yields 4, which in turn forces the letter "D"

Determine Your Birthday - Math Number Trick

Just follow the steps with a calculator orby hand for building math skills!Go ahead and try the trick without cheating!* Add 18 to your birth month*.Multiply by 25*.Subtract 333*.Multiply by 8*.Subtract 554*.Divide by 2*.Add your birth date*.Multiply by 5*.Add 692*.Multiply by 20*.Add only the last two digits of yourbirth year*.Subtract 32940 to get your birthday!The answer’s format is: month/day/year. For example, an answer of123199means that you were born on December 31, 1999. If the answer is not right, you followed the directions incorrectly or lied about your birthday.