Re: Daily question answer

Posted by Khushboo on Feb 15, 2009; 3:28pm
URL: http://discussion-forum.276.s1.nabble.com/Daily-question-tp2328964p2330123.html

Suppose the 3 doors are A1 , A2, A3 and   B - Host opens the door 3

 If the car is behind 1, then host would open either door 2 or 3.


 So, P[ A1/B ] =  P[B/A1] P[A1] / P[B/A1] P[A1] + P[B/A2] P[A2]
                    =  1/2 * 1/3  /  1/2 * 1/3 + 1 * 1/3
                    =  1/3

 then, P [ A1/B ] = 1/3
         P [ A2/B ] = 2/3

 Therefore, having a car in door 2 has a greater advantage.