A pair dice is rolled. What is the probability of getting a sum of 8?
To find the probability of an event, denoted P(E), you need to find the number of possible outcomes of the experiment, n(s) . This is the same as the number if elements in the sample space. You also need to find the number of ways the event can occur, denoted n(E).
Then use the formula p(E) = .
The experiment in this case is the rolling of two dice.
By counting all possible outcomes it is clear that n(s) = 36.
For the event of getting a sum of 8, the number of possible outcomes is 5.
Thus n(E) = 5.
Therefore, P(E) = .