Answer : We know that,

Probability of occurrence of an event

(2, 1), (2, 2), (2, 3), (2, 4), (2, 5), (2, 6),Total outcomes are (1, 1), (1, 2), (1, 3), (1, 4), (1, 5), (1, 6),

(3, 1), (3, 2), (3, 3), (3, 4), (3, 5), (3, 6),

(4, 1), (4, 2), (4, 3), (4, 4), (4, 5), (4, 6) ,

(5, 1), (5, 2), (5, 3), (5, 4), (5, 5), (5, 6) ,

(6, 1), (6, 2), (6, 3), (6, 4), (6, 5), (6, 6)

Desired outcomes are (3, 6), (4, 5), (5, 4), (6, 3), (6, 5) , (5, 6) Total no.of outcomes are 36 and desired outcomes are 6

Therefore, probability of getting total equal to 9 or 11

Conclusion: Probability of getting total equal to 9 or 11, when two dice are rolled is 1/6