# Fourteen Magic Number Tricks

“Fight Against Stupidity And Bureaucracy”

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In previous posts we have had ‘Beautiful Numbers’, ‘Big Numbers’, ‘Unusual Numbers’ and lots of what I called ‘Significant Numbers’.

Today, for a bit of a change, it is the turn of ‘Magic Numbers’, or magic number tricks.

I call them magic numbers because the results of some of them are predictable and on occasions magicians have incorporated them into their magic routines, where, for example, they need their ‘stooge’ to pick a certain card or a certain page in a book and want to give the audience the illusion of a random choice.

Try some of these out. Use them to do a bit of magic yourselves, or to win friends and influence people. Or just to entertain people you like or bore people you don’t like, whichever you think is appropriate.

Anyway I hope you enjoy this selection. You’ll need a calculator if you want to check  them out.

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First Magic Number Trick.

Step 1:  Pick a number,

Step 3:  multiply by 3,

Step 4:  subtract 6,

Step 5:  divide by 3.

You should get the number you started with.

This works for other, larger numbers. This example started with add 2 and multiply 3. But any two numbers work, just multiply them together to get the next number that you subtract.

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Second Magic Number Trick.

Step 1:  Pick a number,

Step 2:  square it (probably need a calculator for big numbers),

Step 3:  add twice the original number,

Step 5:  take the square root (rounding it to the nearest whole number, 7.999… becomes 8),

Step 6:  subtract 1,

You should get the number you started with.

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Third Magic Number Trick.

Step 1:  Pick a number,

Step 2:  square it,

Step 3:  add ten times the original number,

Step 5:  take the square root (rounding to the nearest whole number),

Step 6:  subtract your original number.

The answer should always be 5.

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Third Magic Number Trick.

Here is a slightly more complicated one.

Step 1:  Pick a number between 1 and 100,

Step 3:  multiply by 6,

Step 4:  subtract 3,

Step 5:  divide by 3,

Step 6:  subtract the original number plus 3,

Step 8:  subtract the original number minus 1,

Step 9:  multiply by 7.

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Fourth Magic Number Trick.

Step 1:  Pick a number 1 through 9,

Step 2:  multiply by 12345679 (notice there is no 8 there),

Step 3:  multiply by 9.

Do you see your original number?

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Fifth Magic Number Trick.

Step 1:  Pick a 3-digit number in which the first and last digits differ by more than one,

Step 2:  reverse this number (for example, 531 becomes 135) and subtract the smaller from the larger,

Step 3:  add this number to the reverse of itself.

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Sixth Magic Number Trick.

Step 1: Think of a 3 digit number.

Step 2: Multiply it by 7, then by 11, and then by 13.

for example, if you chose the number 456, your answer would be 456456

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Seventh Magic Number Trick.

Step 1: Think of a 2 digit number.

Step 2: Multiply it by 3, then by 7, then by 13, and then by 37.

You should see your original number repeated three times.

For example, if your number was 45, the answer would be 454545

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Eighth Magic Number Trick.

Step 1: Think of a 5 digit number.

Step 2: Multiply it by 11.

Step 3: Multiply it by 9091.

For example, if the number is 12345, the answer should be 1234512345

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Ninth Magic Number Trick.

If you multiply 1089 by 9 you get 9801. The number has reversed itself!

This also works with 10989 or 109989 or 1099989 and so on.

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Tenth Magic Number Trick.

19 = 1 x 9 + 1 + 9 and 29 = 2 x 9 + 2 + 9.

This also works for 39, 49, 59, 69, 79, 89 and 99.

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Eleventh Magic Number Trick.

2 is the only number that gives the same result added to itself as it does times by itself.

In other words  2 + 2  =  4  =  2 x 2,  or,   (2+2) – (2 x 2) = 0

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Twelfth Magic Number Trick.

If you multiply 21978 by 4 it turns backwards

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Thirteenth Magic Number Trick.

153, 370, 371 and 407 are all the sum of the cubes of their digits.

In other words 153 = 13+53+33,  370 = 33+73+03,  371 = 33+73+13,  153 = 43+03+73,

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Fourteenth Magic Number Trick.

1 divided by 37 = 0•027027027

and

1 divided by 27 = 0•037037037

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## 11 thoughts on “Fourteen Magic Number Tricks”

1. Kenton Lewis says:

Clever post. Really liked the video.

• Thanks. Stuff like that helps to keep me amused.

• It’s ok, I did and they seem to work!

• At least you didn’t kick the can down the road. Thanks for taking the responsibility. 😉

2. I played with some of them, I am a geek that way. They work, you are also a geek. Cool video.

3. I’m no good at math but maybe i could try the first one! Or I could just try them out on other people. What fun!

• That’s the spirit, make others do the work!

4. If you’ll excuse me for a moment, I need to wash the brain ooze off my left cheek. When I come back, can somebody please tell me who the heck I am? 😯

• You ain’t tomorrow’s yet 🙂