quasi
Posts:
11,876
Registered:
7/15/05


Re: Probability Pill
Posted:
Dec 27, 2012 5:47 AM


William Elliot wrote:
>Each day I take 1/2 an aspirin tablet. I bought a bottle of >100 tablets; each day I take out one, if it's whole I break >it half and eat a half and put the other half back: if I pull >out a half tablet I eat it. I was wondering after I break the >last whole one what the expected number of halves are in the >bottle? I assume that any piece I pull out has uniform >probability.
I suspect that the above question is not actually yours.
If that's the case, what is the actual source?
Is it from a poster in another forum? If so, why do you omit mention of the poster and the forum?
Is it from a book or math contest?
Why do you repeatedly post questions that are not your own without giving credit to the source?
In any case, the expected number of halves left when the last whole pill is split is
(199!) / ((4^99)*((99!)^2))
quasi

