RAJITH RAVEENDRANATH wrote:> The explanation given as solution 2
> is wrong as W2W1 and W1W2 are not 2
> separate states as they are indistinguishable
It's a matter of terminology. You may say it's a single state to which one may arrive by two different routes. Then count the number of routes instead of states.
> I have a solution (#3 
) which gives
> the probability as 1/3 (SURPRISED !!)
Nah, nothing surprises me anymore. 
> The bag has equal probabilities of
> having W or B initially. After a white
> counter put in and the two counters drawn
> one after the other, the following
> DISTINGUISHABLE combinations are there -
> WW
> WB
> BW.
>
> The first draw proved to be white.
> If the one inside is indeed white the
> combination we are looking for is WW.
> Probability (by definition) = No. of
> possible occurences/Total no. =
> 1(WW)/3(WW+BW+WB) = 1/3
This I do not understand. You have to discard either WB or BW - I do not know which one is "the first" for you - from your count. So, even according to your scenario, the answer should be 1/2 and not 1/3.
> Mail me your views !!
Please use one of the CTK Exchange forums to post your questions. Please do not use my email.
Thank you,
Alexander Bogomolny
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