Ultraglide
Advanced Member
Canada
299 Posts 
Posted  10/13/2012 : 11:02:17

This is not an easy problem. Consider the probability of drawing a team form the top 14 which is 14/40. Now consider the probability of drawing the second team from the bottom 15 which is 15/39. So the probability of drawing the first two teams from the top and bottom group respectively is (14/40)(15/39). So the probability of not getting a match is 1(14/40)(15/39). Now for the second draw, you have to consider cases: was the first one drawn from the top, middle, or bottom group? From what group was the second one drawn and so on. I don't know where this problem came from but it is a lengthy process if you want to continue. 

