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Question 270008
JEE Mathematics · Medium

Probability: Total probability MCQ

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Total probabilityMediumQuestion 270008

Question

A fair coin is tossed. If heads, one fair die is rolled; if tails, two fair dice are rolled. What is the probability that at least one rolled die shows 6?
  1. A
    17/72
    Correct
  2. B
    7/24
  3. C
    1/6
  4. D
    1/3

Correct answer

17/72

Explanation

Given heads, the probability is 1/61/6. Given tails, it is 1−(5/6)2=11/361-(5/6)^2=11/36. By total probability, P=12(1/6)+12(11/36)=<strong>17/72</strong>P=\frac12(1/6)+\frac12(11/36)=<strong>17/72</strong>.

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