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# Infinite Flips

### #1

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?

### #2

Posted 05 December 2013 - 08:09 AM

**Edited by bonanova, 07 December 2013 - 10:51 AM.**

Replacing first guess with solution

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

- Bertrand Russell

### #3

Posted 05 December 2013 - 06:24 PM

### #4

Posted 07 December 2013 - 10:52 AM

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

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

- Bertrand Russell

### #5

Posted 07 December 2013 - 02:58 PM

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

- Bertrand Russell

### #6

Posted 07 December 2013 - 04:14 PM

### #7

Posted 07 December 2013 - 04:31 PM

Spoiler for a question for bonanova

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

- Bertrand Russell

### #8

Posted 07 December 2013 - 04:33 PM

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

### #9

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.

### #10

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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