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Least number of coin tosses for at least one head with probability above a value

The same question, asked 2 times: 10 May 2023 S2*, 14 May 2026 S2. Every wording below, oldest first.

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  1. Question 1

    10 May 2023 S2

    111
    Minimum number of times a fair coin must be tossed, so that the probability of getting at least one head, is more than 99% is

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  2. Question 2

    14 May 2026 S2

    99
    A coin is tossed n times. The probability of getting a head at least once is greater than 0.80.8, then the least value of n is

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