Toss 2dice, and let the event be the sum of the value of the top faces. The possible outcome are computed inside the table

At the intersection of the row the " toss 1^st die" and the column of " toss the 2^nd die"

Because there are 36 outcomes, the probability of a sum= frequency of the sum/36

Sum          probability

2                 1/36

3                 2/36

4                 3/36

5                 4/36

6                 5/36

7                 6/36

8                 5/36

9                 4/36

10               3/36

11               2/36

12               1/36

Only one of the sums 2 through 12 can occur in a single toss of the die. These are mutually exclusive events. The simple addition rule P (A or B) = P(A) + P(B applies)

Match the item on the left to item on the right

LEFT                                   RIGHT

A. 0.583                              D. P (X at least 7)

B. 0.000                              E. P (X is not 9)

C. 0.889                              F.  P (X = 1)