Re: Plz solve diss..

Posted by cheesecake on Jun 24, 2015; 9:08am
URL: http://discussion-forum.276.s1.nabble.com/Plz-solve-diss-tp7598374p7598384.html

This may be completely wrong.
Total ways in which n people can be seated on 2n chairs will by 2nPn. Now let the first persob be seated on chair 1. 2nd person on chair 3, 3rd person on chair 5 and so on. This can be done in n! ways. Also it is possible that the 1st person was seated on chair 2 instead of chair 1, 2nd person on chair 4 and so on. This happens in n! Ways too. So total number of ways is n!+n! = 2(n!).
So probability is 2(n!) / 2nPn