Two four-sided dice are rolled. One die has the letters A through D. The other has the numbers 1 through 4. Express the event “a roll of the dice will contain the letter A or B” as a set (show each of the possible combinations). What is the probability that a roll will contain an A or a B? Solution The set S = { A1,A2,A3,A4,B1,B2,B3,B4,C1,C2,C3,C4,D1D,D3D4} Let event M =a roll of the dice will contain the letter A or B M = {A1,A2,A3,A4,B1,B2,B3,B4} Probability = 8/16 = 1/2.

1. Two four-sided dice are rolled. One die has the letters A through D. The other has the numbers 1
through 4.
Express the event “a roll of the dice will contain the letter A or B” as a set (show each of the
possible combinations).
What is the probability that a roll will contain an A or a B?
Solution
The set
S = { A1,A2,A3,A4,B1,B2,B3,B4,C1,C2,C3,C4,D1D,D3D4}
Let event M =a roll of the dice will contain the letter A or B
M = {A1,A2,A3,A4,B1,B2,B3,B4}
Probability = 8/16 = 1/2