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#1526 2012-07-23 15:40:24

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,494

Re: Is this cool with you?

New Problem:

A list of 1000 zeroes is created called M. A random number is picked from 1 to 1000. Each time one of these is picked, the zero in the list ( at that index ) is changed to a 1. For instance if the random number is 276 then M[276]=1. What is the average number of random numbers that must be picked to have 200 ones in the list?

A says) 200 of course.

B says) Not likely A the exact answer is C says) I got 251.18725416273654 and that is darn close.

D says) That is what I got!

E says) Nope, I like B's answer.

What is B's answer?


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#1527 2012-07-23 20:45:34

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 3,915

Re: Is this cool with you?

Hi Bobby,

Last edited by phrontister (2012-07-23 21:32:54)


"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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#1528 2012-07-23 22:50:49

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,494

Re: Is this cool with you?

Hi phrontister;


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#1529 2012-07-24 02:44:16

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 3,915

Re: Is this cool with you?

Hi Bobby,


"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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#1530 2012-07-24 02:50:09

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,494

Re: Is this cool with you?

Hi phrontister;


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

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#1531 2012-07-24 04:24:00

gAr
Member
Registered: 2011-01-09
Posts: 3,479

Re: Is this cool with you?

Hi bobbym,


"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

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#1532 2012-07-24 04:41:49

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,494

Re: Is this cool with you?

Hi gAr;


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

#1533 2012-07-24 04:54:26

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 3,915

Re: Is this cool with you?

Hi Bobby,

I found my error with the shortcut and fixed it. Both methods give the same answer.

Last edited by phrontister (2012-07-24 14:28:41)


"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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#1534 2012-07-24 05:04:43

gAr
Member
Registered: 2011-01-09
Posts: 3,479

Re: Is this cool with you?

Hi bobbym,

I think you are right.
I did not try simulation.


"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

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#1535 2012-07-24 07:30:42

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,494

Re: Is this cool with you?

Hi gAr;

Okay, give it a try when you have some time. Thanks for working on the problem.

Hi phrontister;

That is good. Did you know a solution in M earns extra credit? Thanks for looking at the problem.


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

#1536 2012-07-24 12:22:28

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 3,915

Re: Is this cool with you?

Hi Bobby,

Did you know a solution in M earns extra credit?

Xlnt! I'll send you my bank account details if I find an M solution. smile

Should I try one of my methods? If so, which one? Or did you mean your method (but I don't understand yours or gAr's because of my Year 4 high-school maths level).


"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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#1537 2012-07-24 17:11:44

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,494

Re: Is this cool with you?

Hi phrontister;

I meant for a simulation using M.

Should I try one of my methods?

Yes! Either one that you think will be easier to code in M.


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

#1538 2012-07-24 19:17:17

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 3,915

Re: Is this cool with you?

Ok, Bobby, I'll give that a go. Get ready for my cry for help, though, because at this early stage the task seems to be a bit daunting.

I've got no idea whatsoever about how go about it, other than to dive into M's help files with the hope that I can find some examples that relate to what I want to do...which may take a while.


"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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#1539 2012-07-24 19:54:33

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,494

Re: Is this cool with you?

Hi phrontister;

You will do fine. Holler if you need help.


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

#1540 2012-07-25 03:54:06

gAr
Member
Registered: 2011-01-09
Posts: 3,479

Re: Is this cool with you?

Hi bobbym,


"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

Offline

#1541 2012-07-25 07:42:00

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,494

Re: Is this cool with you?

Hi gAr;

If you want to you can. Let me know when and I will make a thread there for yours and phrontister's.


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

#1542 2012-07-26 01:41:09

gAr
Member
Registered: 2011-01-09
Posts: 3,479

Re: Is this cool with you?

Hi bobbym,

Yes, and maybe you too can post your code there so that users can have a choice among the tools of the trade!


"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

Offline

#1543 2012-07-26 01:45:24

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,494

Re: Is this cool with you?

Hi;

Will do!


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

#1544 2012-09-05 22:51:46

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,494

Re: Is this cool with you?

New problem:

What is the diameter of the smallest circle that encloses x^2 + y^2 = 4 and (x - 2)^2 + (y - 4)^2 = 9?


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

#1545 2012-09-06 01:15:30

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,657

Re: Is this cool with you?

Hi bobbym

Last edited by anonimnystefy (2012-09-06 01:15:42)


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#1546 2012-09-06 01:39:36

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,494

Re: Is this cool with you?

Hi anonimnystefy;


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

#1547 2012-09-06 01:52:11

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,657

Re: Is this cool with you?

Hi bobbym


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#1548 2012-09-06 02:19:31

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,494

Re: Is this cool with you?


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

#1549 2012-09-06 10:43:20

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,494

Re: Is this cool with you?

New problem;

What is the area of the smallest equilateral triangle that encloses x^2 + y^2 = 4 and (x - 2)^2 + (y - 4)^2 = 9?


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

#1550 2012-09-24 06:47:50

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 90,494

Re: Is this cool with you?

New Problem:

E says)

The sum

converges slowly. It takes 80,000 terms to get only 8 correct digits past the decimal. B can you speed up the convergence of this series? I know that Mathematica or Maple can get any number of digits for it but I would like to do it myself. What I am looking for is an acceleration of the series convergence.

A says) Hold on E, B isn't the only guy who can do things. I have never been wrong yet have I? Of course not. Just let me say there is no way. Now you can talk B.

B says) Thanks A you are too kind to me. Of course there is a simple way to produce a series that converges faster than that one. All you do is make use of...

C says) There you go again B. Contradicting A. There is a reason A goes first. He is the man! The best! He already said it can not be done.

D says) What is a series?

E says) A comes before B because of the dictionary. I want to hear what B has to say.

A says) I don't.

C says) Agreed!

D says) B, is it true that you are a distant cousin of Torricelli? Not Evangelista, the other one.

B says) Oh boy!?

Can you come up with a faster series that converges to the same value?


In mathematics, you don't understand things. You just get used to them.

I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.

Offline

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