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**phrontister****Real Member**- From: The Land of Tomorrow
- Registered: 2009-07-12
- Posts: 3,847

Hi Bobby,

*Last edited by phrontister (2010-04-10 12:37:58)*

"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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**ZHero****Real Member**- Registered: 2008-06-08
- Posts: 1,889

bobbym wrote:

Hi ZHero;

Sorry, can't even copy my own problem correctly. I have fixed the...

hi Bobbym!

You need to Double Check, Triple Check or say "n times" Check ur posts.

Don't be Sorry... Just Admit ur Mistake and be a lil'bit More Careful from next time!

*Last edited by ZHero (2010-04-09 04:53:26)*

If two or more thoughts intersect with each other, then there has to be a point.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,436

Hi;

For the problem in post # 75

You are both right, A,B,C are all wrong the answer is 8.

**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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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,436

Hi;

If r1, r2 and r3 are the roots of

and a ≠ 0 and

find a.

A says) No solutions.

B says) There are many answers for a but only one integer answer.

C says) There is only one answer for a.

D says) There are many answers but none of them are integers.

Who is right?

**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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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,436

Hi;

How many solutions are there to xyz = 360 when x ≠ y ≠ z and x,y,z > 0 ?

A) says 180

B) says 360

C) says 126

D) says 168

Who is right, hide your answers and back them up.

**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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**phrontister****Real Member**- From: The Land of Tomorrow
- Registered: 2009-07-12
- Posts: 3,847

Hi Bobby,

*Last edited by phrontister (2010-04-22 03:17:50)*

"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,436

That's correct! Very good!

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,436

Hi;

What is the smallest integer that when cubed has it's last 4 digits the same?

A says ) 9999

B says ) There are some that are smaller than that.

C says ) There is only 2 smaller numbers.

Who is right and why?

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**phrontister****Real Member**- From: The Land of Tomorrow
- Registered: 2009-07-12
- Posts: 3,847

Hi Bobby,

*Last edited by phrontister (2010-04-23 12:43:35)*

"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,436

Hi phrontister;

That is correct! What does your LB code look like?

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**phrontister****Real Member**- From: The Land of Tomorrow
- Registered: 2009-07-12
- Posts: 3,847

Hi Bobby,

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,436

Hi;

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**phrontister****Real Member**- From: The Land of Tomorrow
- Registered: 2009-07-12
- Posts: 3,847

Hi Bobby,

That's a neat trick!

Same answers as mine, and it took 18% less time.

*Last edited by phrontister (2010-04-24 00:10:10)*

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,436

Hi phrontister;

Usually string operations, like converting integers to strings are very slow in almost every language. When possible work with integers, they are faster.

A tough one so be careful:

What is the smallest n, that n^3 has 4444 at the end?

A says ) No cube has 4444 on the end.

B says ) Of course there is some cube with 4444 on the end.

C says ) There are an infinite number of them but they are all 30 digits or more.

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**phrontister****Real Member**- From: The Land of Tomorrow
- Registered: 2009-07-12
- Posts: 3,847

Hi Bobby,

*Last edited by phrontister (2010-04-24 03:58:21)*

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,436

Hi phrontister;

That is correct, can you give an old man a little help with your explanation? I am not following it.

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**phrontister****Real Member**- From: The Land of Tomorrow
- Registered: 2009-07-12
- Posts: 3,847

Hi Bobby,

*Last edited by phrontister (2010-04-25 11:22:03)*

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,436

Hi phrontister;

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**ZHero****Real Member**- Registered: 2008-06-08
- Posts: 1,889

*Last edited by ZHero (2010-04-24 19:06:33)*

If two or more thoughts intersect with each other, then there has to be a point.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,436

Hi ZHero;

Your solution is a real killer. It is devastating. I didn't think of that. Looks like a large happy face eating the earth.

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**ZHero****Real Member**- Registered: 2008-06-08
- Posts: 1,889

yeah.. that was the result when i tried to run a simple program in

Language on my

If two or more thoughts intersect with each other, then there has to be a point.

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**phrontister****Real Member**- From: The Land of Tomorrow
- Registered: 2009-07-12
- Posts: 3,847

Hi Bobby,

I had already done something similar to yours:

*Last edited by phrontister (2010-04-25 11:29:16)*

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,436

There is a shorter proof of this that doesn't use a computer. Unfortunately I can't remember what it is or how I derived it. I will post it when I do. Good work, by the way.

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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**phrontister****Real Member**- From: The Land of Tomorrow
- Registered: 2009-07-12
- Posts: 3,847

Hi Bobby,

*Last edited by phrontister (2010-04-25 15:17:17)*

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,436

Hi phrontister;

Do you have some idea in mind?

Of course that result can be rigorously obtained, but who cares?

Combinatorics is Algebra and Algebra is Combinatorics.

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