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Flip Until Heads Puzzle

Technically, there's no ceiling on the number of flips. You could theoretically flip tails forever. But long streaks get exponentially rarer, and this infinite series sums to 2.

A fast way of calculating the expected number of flips is:

Expected flips = 1/p,
where p is the probability of heads

Expected flips = 1/0.5 = 2

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