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## #126 2012-03-07 04:29:58

gAr
Star Member

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### 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."

## #127 2012-03-07 04:36:38

bobbym

Online

### Re: Bafflers?

Hi gAr;

Not too difficult but cute problem.

In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #128 2012-03-07 04:46:20

bobbym

Online

### Re: Bafflers?

Hi hammana;

In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #129 2012-03-07 04:59:56

gAr
Star Member

Offline

### 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."

## #130 2012-03-07 05:09:07

bobbym

Online

### 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.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #131 2012-03-07 06:16:06

anonimnystefy
Real Member

Online

### Re: Bafflers?

Hi bobbym

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

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón

## #132 2012-03-07 07:04:05

hammana
Member

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### 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.

## #133 2012-03-07 07:36:49

anonimnystefy
Real Member

Online

### Re: Bafflers?

Hi bobbym

For #1 I got an explicit formula

Is it correct?

Last edited by anonimnystefy (2012-03-07 07:38:33)

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón

## #134 2012-03-07 07:44:13

hammana
Member

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### 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

## #135 2012-03-07 09:47:27

bobbym

Online

### 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.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #136 2012-03-07 09:52:15

anonimnystefy
Real Member

Online

### Re: Bafflers?

Hi bobbym

I did it using the magnificent GF's.

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón

## #137 2012-03-07 09:58:12

bobbym

Online

### Re: Bafflers?

Well let me see.

In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #138 2012-03-07 10:02:39

anonimnystefy
Real Member

Online

### 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.

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón

## #139 2012-03-07 10:07:17

bobbym

Online

### Re: Bafflers?

Then Thursday evening you will do it.

In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #140 2012-03-07 10:08:47

anonimnystefy
Real Member

Online

### Re: Bafflers?

Sure! Can I expect more problems soon.

And you were right, these ones are easier.

Last edited by anonimnystefy (2012-03-08 09:15:40)

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón

## #141 2012-03-07 10:18:20

bobbym

Online

### 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.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #142 2012-03-08 08:20:26

anonimnystefy
Real Member

Online

### 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.

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón

## #143 2012-03-08 08:36:09

bobbym

Online

### Re: Bafflers?

I am waiting for your generating function...

In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #144 2012-03-08 08:45:47

anonimnystefy
Real Member

Online

### 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.

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón

## #145 2012-03-08 08:50:47

bobbym

Online

### 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.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #146 2012-03-08 08:57:34

anonimnystefy
Real Member

Online

### 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.

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón

## #147 2012-03-08 08:58:57

bobbym

Online

### Re: Bafflers?

Who will you compete against?

In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #148 2012-03-08 09:07:32

anonimnystefy
Real Member

Online

### Re: Bafflers?

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

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón

## #149 2012-03-08 09:08:14

bobbym

Online

### Re: Bafflers?

How have you prepared?

In mathematics, you don't understand things. You just get used to them.
Probability is the most important concept in modern science, especially as nobody has the slightest notion what it means.
90% of mathematicians do not understand 90% of currently published mathematics.

## #150 2012-03-08 09:10:00

anonimnystefy
Real Member

Online

### Re: Bafflers?

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

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“A secret's worth depends on the people from whom it must be kept.” ― Carlos Ruiz Zafón