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Infinite Flips


Best Answer bonanova, 11 December 2013 - 06:40 PM

Spoiler for Suggestive proof

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23 replies to this topic

#1 BMAD

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Posted 04 December 2013 - 02:24 AM

Given a coin with probability p of landing on heads after a flip, what is the probability that the number of heads will ever equal the number of tails assuming an infinite number of flips?


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#2 bonanova

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Posted 05 December 2013 - 08:09 AM

Spoiler for For starters


Edited by bonanova, 07 December 2013 - 10:51 AM.
Replacing first guess with solution

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#3 plainglazed

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Posted 05 December 2013 - 06:24 PM

Spoiler for I should know better...


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#4 bonanova

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Posted 07 December 2013 - 10:52 AM

On further thought, I think my answer gives only a lower bound.


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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
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#5 bonanova

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Posted 07 December 2013 - 02:58 PM

Spoiler for Final answer


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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

#6 plainglazed

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Posted 07 December 2013 - 04:14 PM

Spoiler for a question for bonanova


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#7 bonanova

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Posted 07 December 2013 - 04:31 PM

Spoiler for a question for bonanova

Spoiler for Thats right

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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

#8 BMAD

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Posted 07 December 2013 - 04:33 PM

Spoiler for edit--forgot spoiler

Edited by BMAD, 07 December 2013 - 04:33 PM.

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#9 plainglazed

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Posted 07 December 2013 - 04:44 PM

@ bonanova - but infinity flips is a fair many more than "a large number of flips"

 

@ BMAD - someone but not everyone?

 

hopefully my responses here are taken as meant to be - lack of full comprehension of very large numbers - and not as deviating from the spirit of the riddle.


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#10 BMAD

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Posted 07 December 2013 - 05:09 PM

It depends on how you splice the question.  essentially we could have one person play 1,000,000 and they will have a low but existing probability of being even.  We could also have 500,000 people play twice and have again a low but existing probability of being even.


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