Games and stopping · Playoffs · difficulty 3 of 5
How long the series runs
Two teams play a playoff series that ends as soon as one of them has 4 wins, so it lasts at most 7 games. Team A wins each game with probability 0.5, independently of the other games. What is the expected number of games played?
Answer with an expected value. First lock in a gut guess with an 80% range, then solve it properly, then watch a simulation settle on the truth.
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