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**lovesmath** A business office orders paper supplies from one of three vendors, v1, v2, or v3. Orders are randomly to be placed to those three vendors on two successive days, one order per day. Thus (v2, v3) might denote that vendor v2 gets the order on the first day and vendor v3 gets the order on the second day.

a) Describe the sample space of this experiment in ordered pairs on two successive days.

b) Assume the vendors are selected at random to fill the order. Assign a probability to each elementary outcome.

c) Let A denote the event that the same vendor gets both orders and B the event that the second vendor, v2, gets at least one order. Find P(A), P(B), P(AB), and P(AUB).

My answers:

a) S = {(v1, v1), (v1, v2), (v1, v3), (v2, v1), (v2, v2), (v2, v3), (v3, v1), (v3, v2), (v3, v3)}

b) The probability of each outcome is 1/9.

c) P(A) = 1/3. P(B) = 5/9.