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    Question

    What is the probability of getting atleast one head if

    three unbiased coins are tossed?
    A 7/8 Correct Answer Incorrect Answer
    B 1/2 Correct Answer Incorrect Answer
    C 5/8 Correct Answer Incorrect Answer
    D 8/9 Correct Answer Incorrect Answer
    E 5/6 Correct Answer Incorrect Answer

    Solution

    The sample space is = {TTT, TTH, THT, HTT, THH, HTH, HHT, HHH} Let E is the event of getting atleast one head Then E = {TTH, THT, HTT, THH, HTH, HHT, HHH} P(E) = n(E) / n(S) = 7/8.

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