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#126 2012-03-06 05:29:58

gAr
Member
Registered: 2011-01-09
Posts: 3,462

Re: Bafflers?

Hi bobbym,

Thank you!


"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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#127 2012-03-06 05:36:38

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 81,431

Re: Bafflers?

Hi gAr;

Not too difficult but cute problem.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

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#128 2012-03-06 05:46:20

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 81,431

Re: Bafflers?

Hi hammana;


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

Online

#129 2012-03-06 05:59:56

gAr
Member
Registered: 2011-01-09
Posts: 3,462

Re: Bafflers?

Hi,

Yes, it's a good problem.


"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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#130 2012-03-06 06:09:07

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 81,431

Re: Bafflers?

Hi;

Glad you and anonimnystefy had some fun with it.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

Online

#131 2012-03-06 07:16:06

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,812

Re: Bafflers?

Hi bobbym

It's a nice problem, and the first one of yours I solved successfully!


“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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#132 2012-03-06 08:04:05

hammana
Member
Registered: 2012-03-02
Posts: 48

Re: Bafflers?

The average value calculated from the table (post 125) is 3.76
We could also say that the number of white marbles is multiplied by .75  at each operation so the final result is :
50*(0.75)^9 =3.7541, This method does not seem very rigorous, but the result is practically identical to the simulation result.

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#133 2012-03-06 08:36:49

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,812

Re: Bafflers?

Hi bobbym

For #1 I got an explicit formula

Is it correct?

Last edited by anonimnystefy (2012-03-06 08:38:33)


“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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#134 2012-03-06 08:44:13

hammana
Member
Registered: 2012-03-02
Posts: 48

Re: Bafflers?

Results given in post 125 are wrong because i assumed that the replacement operation was carried 9 times. A new simulation assuming the replacement carried 10 times gives an aveerage of 2.812 and 50*(0.75)^10=2.8157

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#135 2012-03-06 10:47:27

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 81,431

Re: Bafflers?

Hi anonimnystefy;

Yes that is correct! Very good.

Hi hammana;

Very good answer! Well done.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

Online

#136 2012-03-06 10:52:15

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,812

Re: Bafflers?

Hi bobbym

I did it using the magnificent GF's.


“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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#137 2012-03-06 10:58:12

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 81,431

Re: Bafflers?

Well let me see.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

Online

#138 2012-03-06 11:02:39

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,812

Re: Bafflers?

Are you really gonna make we swype all that? I'm probably not gonna be able to use my laptop or my desktop till thursday evening.


“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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#139 2012-03-06 11:07:17

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 81,431

Re: Bafflers?

Then Thursday evening you will do it.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

Online

#140 2012-03-06 11:08:47

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,812

Re: Bafflers?

Sure! Can I expect more problems soon.

And you were right, these ones are easier.

Last edited by anonimnystefy (2012-03-07 10:15:40)


“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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#141 2012-03-06 11:18:20

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 81,431

Re: Bafflers?

As soon as I find one. I can not guarantee they will all be easy.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

Online

#142 2012-03-07 09:20:26

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,812

Re: Bafflers?

I wonder if it will be before or after thursday night.And they do not have to be easy, just not to be very hard.


“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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#143 2012-03-07 09:36:09

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 81,431

Re: Bafflers?

I am waiting for your generating function...


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

Online

#144 2012-03-07 09:45:47

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,812

Re: Bafflers?

Hi bobbym

It's probably gonna be on thursday afternoon after all.I am finishing with studying tomorrow and then I'm a free man for the next week.


“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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#145 2012-03-07 09:50:47

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 81,431

Re: Bafflers?

But this is only Wednesday. Why are you free for a week?


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

Online

#146 2012-03-07 09:57:34

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,812

Re: Bafflers?

From the thursday evening to the sunday evening of the next week I'm free.on sunday I have a physics competition so I'm not going to school on friday, and the next week I'm off because I have a national mathematics competition.


“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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#147 2012-03-07 09:58:57

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 81,431

Re: Bafflers?

Who will you compete against?


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

Online

#148 2012-03-07 10:07:32

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,812

Re: Bafflers?

Against other grade 10 students from the while Serbia that passed the regionals.


“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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#149 2012-03-07 10:08:14

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 81,431

Re: Bafflers?

How have you prepared?


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

Online

#150 2012-03-07 10:10:00

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,812

Re: Bafflers?

I have but I have till the next week's Friday to prepare as much as I can.


“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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