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**John E. Franklin****Member**- Registered: 2005-08-29
- Posts: 3,562

Pretty neat, huh?

**igloo** **myrtilles** **fourmis**

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,705

Hi John;

How are you? I cannot see what you did.

**In mathematics, you don't understand things. You just get used to them.Of course that result can be rigorously obtained, but who cares?Combinatorics is Algebra and Algebra is Combinatorics.**

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**John E. Franklin****Member**- Registered: 2005-08-29
- Posts: 3,562

The puzzle is what is 27 times 37 ? (pretty neat huh? the answer!!)

**igloo** **myrtilles** **fourmis**

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**Mariner****Member**- Registered: 2010-06-16
- Posts: 35

John E. Franklin wrote:

The puzzle is what is 27 times 37 ? (pretty neat huh? the answer!!)

the wonders of multiplication lol

*Last edited by Mariner (2011-02-15 13:00:56)*

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**John E. Franklin****Member**- Registered: 2005-08-29
- Posts: 3,562

**igloo** **myrtilles** **fourmis**

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,705

Hi John;

Yep, because of

**In mathematics, you don't understand things. You just get used to them.Of course that result can be rigorously obtained, but who cares?Combinatorics is Algebra and Algebra is Combinatorics.**

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**John E. Franklin****Member**- Registered: 2005-08-29
- Posts: 3,562

Yes, that's true!!! Bobby, I learnt that once a long time ago...

By the way, I just watched a short video on a short cut way

to multiply two numbers inclusively between 11 and 19.

Here's an example:

Take 14 times 17, which we all know is 238 by heart anyway by now, but anyhow,

simply add 7 to 14 and get 21. Tack a zero on the

end of 21 for 210. Then to finish, add on to the

210, 4 times 7 or 28 for 238, wow!!! I'll put this in

"This is Cool" too, since it is so wonderful!!

**igloo** **myrtilles** **fourmis**

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**BT****Member**- Registered: 2005-10-06
- Posts: 7

Nice math trick!

Here are more to enjoy:

http://www.pedagonet.com/maths/mathtricks.htm

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**alexa.pete9****Member**- Registered: 2011-04-18
- Posts: 11

Start with any two-digit number. Multiply each digit by itself then add these answers. Do the same thing to this new number and so on until something happens. For example 32 becomes 9+4 which is 13, 13 becomes 1+9 which is 10, 10 becomes 1+0 =1. This one ends at 1. What else happens when you start with different numbers?

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**John E. Franklin****Member**- Registered: 2005-08-29
- Posts: 3,562

@alexa.pete9

I'll try 33:

9 + 9 = 18

1 + 64 = 65

36 + 25 = 61

36 + 1 = 37

9 + 49 = 58

25 + 64 = 89

64 + 81 = 145

1 + 16 + 25 = 42

16 + 4 = 20

4 + 0 = 4

maybe that's the answer...

16 = 16

1 + 36 = 37

9 + 49 = 58

I'm starting to go in a circle now...

**igloo** **myrtilles** **fourmis**

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**mathaholic****Member**- From: Juliania
- Registered: 2012-11-29
- Posts: 2,845
- Website

999

999

999

"Double the fun, double the thrill, double the coolness" - Julianthewiki

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