Look at the table of all possible rolls of two dice.
Chart
Table
12345611, 11, 21, 31, 41, 51, 622, 12, 22, 32, 42, 52, 633, 13, 23, 33, 43, 53, 644, 14, 24, 34, 44, 54, 655, 15, 25, 35, 45, 55, 666, 16, 26, 36, 46, 56, 6
Count the number of elements in each event to find
n(A), n(B), and n(A and B).
n(A)
