New Enroll in RBI Grade B New Batch - Starts on May 21

    Question

    A dice was rolled 3 times. What is the probability of

    getting 5 at least once?
    A 124 / 216 Correct Answer Incorrect Answer
    B 1 / 216 Correct Answer Incorrect Answer
    C 9 / 216 Correct Answer Incorrect Answer
    D 91 / 216 Correct Answer Incorrect Answer
    E 125 / 216 Correct Answer Incorrect Answer

    Solution

    n = 3 p (success) = 1/6 q (failure) = 5/6 P (getting 5 at least once ) = 1 – P ( not getting 5) P (not getting 5 ) = 5/6 * 5/6 * 5/6 = 125 / 216 (3C0 p0 q3-0) P (getting 5 at least once ) = 1 – 125 / 216 = 91 / 216

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