@dave: yes it seems so that 17/18 is correct...I deduced it from the cond prob formula..
I have a minor doubt in general ....why prob( 2nd toss is a head given that a head occurred in the first toss ) doesnt seem same as p( head in first toss and head in second toss with fair coin) +p(head in first toss and head in second toss with unfair coin)? is it due to the fact that we are not looking at the same sample space in both cases?i am not able to visualise the difference in general..this is also the reason why most of the people said earlier 17/80 as the answer.... moreover, if the question was exactly the same except in that it was NOT mentioned that heads occurred previously , what would the prob of getting a head in the second toss? would it be P( of getting tail in first toss and head in second toss given that fair coin is chosen) +P( of getting head in first toss and head in second toss given that fair coin is chosen) +P( getting heads in first toss and heads in second toss given that unfair coin is chosen) ? this for any toss turns out to be 3/5 ....can u explain the logic abt why it always gives 3/5? On Tue, Aug 9, 2011 at 7:37 AM, raj kumar <[email protected]> wrote: > plz reply am i right or wrong > > -- > You received this message because you are subscribed to the Google Groups > "Algorithm Geeks" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to > [email protected]. > For more options, visit this group at > http://groups.google.com/group/algogeeks?hl=en. > -- "People often say that motivation doesn't last. Well, neither does bathing - that's why we recommend it daily." -- You received this message because you are subscribed to the Google Groups "Algorithm Geeks" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en.
