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#1 2014-10-17 18:09:32
Coins - Expectancy
A Kaboobly Dooist discovers an infinite pool of coins with $1, $2 and $5 coins distributed uniformly in it. He takes a coin at random from the pool and puts it in his bag. He does so until the sum of the values of all coins in his bag is equal to or more than $200.
If the expected number of $1 coins is n, what is the value of floor(10*n)?
'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.
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#2 2014-10-18 10:59:02
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Coins - Expectancy
Hi;
Can you please change that question to a link, so that I can answer it.
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#3 2014-10-18 12:30:32
Re: Coins - Expectancy
The question is original. So, I have the right to post it anywhere.
I cannot change it to a link because the question is not available elsewhere.
Last edited by Agnishom (2014-10-18 12:31:37)
'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.
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#4 2014-10-18 21:33:02
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Coins - Expectancy
Yes, but I have answered it at B. A google search can find that question right here. Each additional answer lowers the value of mine. It was already less than 100 when I answered it.
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#5 2014-10-18 22:38:58
Re: Coins - Expectancy
Each additional answer lowers the value of mine. It was already less than 100 when I answered it.
It does not affect your score once you answer it.
I did not think it should be of value > 100
There is a subtle difference between that question and this one. See the last line of the question.
Last edited by Agnishom (2014-10-18 22:40:04)
'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.
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#6 2014-10-18 22:48:03
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Coins - Expectancy
Hi;
I did not think it should be of value > 100
I disagree, there are currently only 10 people who have solved that problem. I would give it a value of 200.
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#7 2014-10-18 23:14:08
Re: Coins - Expectancy
Are you sure?
'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.
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#8 2014-10-18 23:18:26
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Coins - Expectancy
Hi;
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
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#9 2014-10-19 02:48:33
Re: Coins - Expectancy
New Problem Statistics-
14 views (100%) 8 attempts (57%) 2 solvers (14%)
(so far)
Last edited by Agnishom (2014-10-19 02:48:47)
'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.
Offline
#10 2014-10-19 03:18:22
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: Coins - Expectancy
What new problem?
In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.
Offline
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