Expectation · Coin flips · difficulty 2 of 5
Heads and tails both
You flip a coin that lands heads with probability 0.5, independently each time, until you have seen at least one heads and at least one tails. What is the expected number of flips?
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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