At Least One: Repeated Chances and Tries Needed

Chance on each try e.g. 1 in 20, 5% or 1/20

Number of tries

Tries needed for a chance of %

and for %

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From the book, Chapter 3. The 1-in-20 scratch cards: 20 cards give 64.2% for at least one win, not 100%, and 35.8% of the time none. 14 cards give an even chance (51.2%) and 45 give 90% (90.1%). The Chevalier de Méré’s bets: a six in four rolls is 51.8%; a double six in 24 rolls of two dice is 49.1%.

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