Denote the probability by p.

p=n/d , where

n(umerator)=8*7*6*5 (1st sup. team has 8 choices, 2nd 7 etc)

d(enominator)= 8^4 (independent choice -each team in one of the houses)

p=n/d =7*6*5/(8^3)=105/256 i.e. slightly over 40%

blackjack

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