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Counting & ProbabilityHardProbability Fundamentals & Geometric Probability

Probability Fundamentals & Geometric Probability · Hard problem

A fair die is rolled twice independently. Let AA be the event “the first roll is even” and BB the event “the sum of the two rolls is 77.” The probability of A∩BA\cap B is mn\dfrac{m}{n}. Find m+nm+n (and note whether AA and BB are independent).