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#1901 2012-11-02 00:50:45

ShivamS
Member
Registered: 2011-02-07
Posts: 3,445

Re: What do you think?

Hidden message abuse!

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#1902 2012-11-02 00:53:21

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 82,672

Re: What do you think?

Hi Shivamcoder3013;

In this thread because other people may want to work on the problems without actually seeing anyone else's work we use hidden replies.


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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#1903 2012-11-04 00:04:00

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 3,819

Re: What do you think?

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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#1904 2012-11-04 00:25:08

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 82,672

Re: What do you think?

Hi phrontister;


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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#1905 2012-11-04 00:40:04

phrontister
Real Member
From: The Land of Tomorrow
Registered: 2009-07-12
Posts: 3,819

Re: What do you think?

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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#1906 2012-11-04 00:45:54

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 82,672

Re: What do you think?

Hi phrontister;


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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#1907 2012-11-04 10:00:47

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,860

Re: What do you think?

Hi bobbym

Got any expectation problems?


“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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#1908 2012-11-04 10:20:39

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,860

Re: What do you think?

bobbym wrote:

New problem!

The probability of 1 kid is 1/6. Two kids is 1/3. Three kids is 1/3 and four kids is 1 / 6. Everyone gets married and has kids.
What is the chance that a couple has exactly 5 grandkids?

A says 1 / 8
B says 4 / 129
C says (1 / 9)^4
D says ( 1 / 3 )^5

What if they have only one child and that child has 5 of his own childeren? We aren't given the probability of 5 children...

Last edited by anonimnystefy (2012-11-04 10:43:52)


“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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#1909 2012-11-04 10:31:09

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 82,672

Re: What do you think?

Yikes! What in the name of a holy yoctometer are you talking about?


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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#1910 2012-11-04 10:32:29

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,860

Re: What do you think?

Seems you missed post #1907.

I dug that problem from this thread...


“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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#1911 2012-11-04 10:36:25

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 82,672

Re: What do you think?

Hmmm, and now you are getting your just reward!


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.

Offline

#1912 2012-11-04 10:38:42

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,860

Re: What do you think?

I don't understand...


“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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#1913 2012-11-04 10:40:02

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 82,672

Re: What do you think?

Do you not know my age? Are ye unaware of the aging process?


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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#1914 2012-11-04 10:45:14

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,860

Re: What do you think?

bobbym wrote:

Do you not know my age? Are ye unaware of the aging process?

Well, you told me you were 9,99 and 92. I'm not sure which (if not all) version to believe. And yes, I am aware of it... What does that have to do with what I asked you?


“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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#1915 2012-11-04 10:49:10

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 82,672

Re: What do you think?

Well, us old people we forget things. Everyday I lose a couple of neurons and along with them a fact or two. I used to know what the heck that problem was talking about but I forgot. That is the price you pay for not answering problems promptly.

But if I had to bet my oatmeal on someone, I would bet on B! That there is one smart fella!


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.

Offline

#1916 2012-11-04 10:51:53

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,860

Re: What do you think?

bobbym wrote:

Well, us old people we forget things. Everyday I lose a couple of neurons and along with them a fact or two. I used to know what the heck that problem was talking about but I forgot. That is the price you pay for not answering problems promptly.

But if I had to bet my oatmeal on someone, I would bet on B! That there is one smart fella!

If you read the problem you will see that we are not given the probability that a couple has 5 children...


“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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#1917 2012-11-04 10:54:45

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 82,672

Re: What do you think?

I do not think you need that information. Four children could marry and produce 5 grandchildren could they not?


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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#1918 2012-11-04 10:57:58

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,860

Re: What do you think?

But for the expected value, I need to include all possibilities of getting 5 grandchildren including having 5 children, each having 1 child and having only 1 child who has 5 children of his own. Thus, I need the information about the probability of having 5 children...


“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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#1919 2012-11-04 11:03:52

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 82,672

Re: What do you think?

Who said anything about expected value?


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.

Offline

#1920 2012-11-04 11:07:00

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,860

Re: What do you think?

Sorry, probability. But we still need the probability of having 5 children...

Last edited by anonimnystefy (2012-11-04 11:12:26)


“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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#1921 2012-11-04 11:09:57

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 82,672

Re: What do you think?

It is not necessary to know that. You can derive it from the other information.


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.

Offline

#1922 2012-11-04 11:13:05

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,860

Re: What do you think?

But then the problem gets much tougher...


“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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#1923 2012-11-04 11:15:50

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 82,672

Re: What do you think?

Not necessarily, if you remember the methods you have been taught. If you remember Richard.


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.

Offline

#1924 2012-11-04 11:25:30

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,860

Re: What do you think?

Feynmen? You only mentioned that story where he used DUIS.


“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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#1925 2012-11-04 11:31:10

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 82,672

Re: What do you think?

Nope! That story is not just for DUIS. It says a lot more than that. Feynmann is telling us something important there...


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.

Offline

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