Bee H. 1 Expert Answer If you roll a single die there are 6 possible outcomes (1,2,3,4,5,6), 2 of which are greater than 4. So in a single roll the probability of getting a number greater than 4 is 2/6 = 1/3. If you roll two dice, these are independent events so the probability that roll 1 is greater than 4 and roll 2 is greater than 4 is the product of each individual event, so P(both > 4) = P(roll 1 > 4) * P(roll 2 > 4) = (1/3) * (1/3) = 1/9 1) 1/3
2) 1/2
3) 1/12
4) None of these
Solution: Option (2) 1/2 If two dice are thrown, the total number of sample space = 36 Let A be the event that the first die contains 4,P(A) = {(4,1),(4,2), (4,3), (4,4), (4,5), (4,6)} = 6/36 Let B be the event that the numbers greater than 7, P(B) = {(4, 4)(4, 5)(4,6) (5,3)(5,4)(5,5)(5,6) (6,2) (6,3)(6,4)(6,5)(6,6)} P(A∩B) = 3/36 Hence, P(B/A) = P(A∩B)/P(A) = (3/36) /(6/36) =3/6 = 1/2.
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