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#51 2010-01-15 04:50:39

JaneFairfax
Member
Registered: 2007-02-23
Posts: 6,868

Re: What do you think?

Yes, of course.
should be 11.75. (9.75 is what both sides of the equation should be equal to.) Sorry, got confused.


Q: Who wrote the novels Mrs Dalloway and To the Lighthouse?

A: Click here for answer.

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#52 2010-01-15 05:15:55

bobbym
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From: Bumpkinland
Registered: 2009-04-12
Posts: 86,366

Re: What do you think?

No problem.


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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#53 2010-01-16 12:45:27

bobbym
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From: Bumpkinland
Registered: 2009-04-12
Posts: 86,366

Re: What do you think?

HI;

Problem #13:

From the set {A,B,C,D,F,G,H,I,J,K,L} , if the first 6th tuple is AAAAAA and the 10000th 6th tuple is {A,A,I,G,I,A} what is the millionth 6th tuple?


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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#54 2010-01-16 13:40:30

JaneFairfax
Member
Registered: 2007-02-23
Posts: 6,868

Re: What do you think?

Last edited by JaneFairfax (2010-01-16 13:42:49)


Q: Who wrote the novels Mrs Dalloway and To the Lighthouse?

A: Click here for answer.

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#55 2010-01-16 15:52:35

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,366

Re: What do you think?

Hi Jane;

Correct! Good answer!


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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#56 2010-01-18 07:23:32

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,366

Re: What do you think?

Hi;
Problem #14:

From the same set as in #53 what position does LHBICF occupy?


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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#57 2010-01-18 07:35:28

JaneFairfax
Member
Registered: 2007-02-23
Posts: 6,868

Re: What do you think?


Q: Who wrote the novels Mrs Dalloway and To the Lighthouse?

A: Click here for answer.

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#58 2010-01-18 07:38:05

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,366

Re: What do you think?

Yep! Good job!


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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#59 2010-01-18 21:59:28

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,366

Re: What do you think?

Hi;


Problem #15:

What is the longest string of consecutive positive numbers that when added equal 2009?
Watch it it can be tricky.

This is the one I got. Is it the longest? No peeking!


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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#60 2010-01-19 00:45:23

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

Re: What do you think?

Hi Bobby,

I got the same as you, and did it like

Last edited by phrontister (2010-01-19 04:41:38)


"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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#61 2010-01-19 07:58:39

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,366

Re: What do you think?

Good! The question now is simple: Is there a problem that I can get that Jane or you can't get almost before I finish posting it?


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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#62 2010-01-19 09:28:23

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

Re: What do you think?

Hi Bobby,

Is there a problem that I can get that Jane or you can't get almost before I finish posting it?

For Jane, I think your only hope is to work out her sleep pattern and to post your puzzle just after she's gone to bed.

For me, just post anything that needs maths knowledge above year 4 high school level...but there's also a good chance that I've forgotten what I learnt up to that stage too.

Last edited by phrontister (2010-01-19 22:40:22)


"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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#63 2010-01-20 11:48:27

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,366

Re: What do you think?

OK, here is one that will stump ye!

Problem #16:

How many total integer solutions are there to the equations?

a + b + c + d + e + f = r

with r = 0,1,2,3,4,...60

f >= e >= d >= c >= b >= a >= 0

a,b,c,d,e,f < 11

Hint: It has been disguised to be difficult.


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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#64 2010-01-20 13:46:46

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

Re: What do you think?

Hi Bobby,

How many total integer solutions are there to the equations?

Is the answer

?


"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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#65 2010-01-20 13:49:11

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

Re: What do you think?

Hey! Did you add "a,b,c,d,e,f < 11" later, Bobby? Maybe I missed seeing that... (I'll have to look at that later).


"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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#66 2010-01-20 13:50:34

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,366

Re: What do you think?

Hi phrontister;

Yes, I did, sorry for the confusion. I have also edited out the error you spotted. Thanks for pointing it out. I cleaned your quote up as well, otherwise it would have looked like you were talking about a phantom mistake.


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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#67 2010-01-20 13:52:25

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

Re: What do you think?

How close was my first answer? (Just wanna see if I'm on the right track)


"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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#68 2010-01-20 13:53:45

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,366

Re: What do you think?

Not close.


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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#69 2010-01-20 13:55:08

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

Re: What do you think?

Oops! Wonder where I went wrong. Back to the drawing board! (later)


"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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#70 2010-01-20 14:08:03

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

Re: What do you think?

bobbym wrote:

f >= e >= d >= c >= b >= a >= 0

Is ">=" the same as "≥"? That's what I took it to be.

Edit: And that:-
f ≥ e,
e ≥ d,
d ≥ c,
c ≥ b,
b ≥ a, and
a ≥ 0

a,b,c,d,e,f < 11

I take it that means that each of those letters is less than 11.

Last edited by phrontister (2010-01-20 14:11:49)


"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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#71 2010-01-20 14:10:20

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,366

Re: What do you think?

Yes, you have the constraints 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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#72 2010-01-20 14:15:53

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

Re: What do you think?

bobbym wrote:

Not close.

Do you mean that it wasn't close to the answer to the original problem before that additional constraint?


"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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#73 2010-01-20 14:21:44

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,366

Re: What do you think?

Hi;

Without the constraint that they are all less than 11 the answer would be much larger, 241502 solutions.


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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#74 2010-01-20 14:23:26

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

Re: What do you think?

Yes...I just saw where I went wrong (overlooked 'some' options).


"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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#75 2010-01-21 21:21:28

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 86,366

Re: What do you think?

Here is an easy one:

Problem #17:

Prove that:


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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