Question

Which NCAA college basketball conference has the higher probability of having a team play in a college basketball's national championship game? Over the last 20 years, the Atlantic Coast Conference (ACC) ranks first by having a team in the championship game 10 times. The Southeastern Conference (SEC) ranks second by having a team in the championship game 8 times. However, both conferences have had teams in the championship game only one time, when Arkansas (SEC) beat Duke (ACC) 76–70 in 1994 (NCAA website, April 2009). Use these data to estimate the following probabilities.

a. What is the probability the ACC will have a team in the championship game?
b. What is the probability the SEC will have team in the championship game?
c. What is the probability the ACC and SEC will both have teams in the championship game?
d. What is the probability at least one team from these two conferences will be in the championship game? That is, what is the probability a team from the ACC or SEC will play in the championship game?
e. What is the probability that the championship game will not a have team from one of these two conferences?

Answer 1

A)P(ACC has a team in the championship game) = 0.5

B)P(SEC has a team in the championship game) = 0.4

C)P(both ACC & SEC having teams in the championship games) = 0.05

D)P(ACC or SEC) = 0.85

E)P(not ACC or SEC) = 0.15

Explanation:

A) We are told that in the last 20 years, ACC has had a team in the championship game for 10 times.

Thus;

P(ACC has a team in the championship game) = 10/20 = 0.5

B) SEC has a team in the championship game 8 times in the last 20 years;

Thus;

P(SEC has a team in the championship game) = 8/20 = 0.4

C) since both ACC and SEC have had teams in the championship game for the past 20 years, then;

P(both ACC & SEC having teams in the championship games) = 1/20 = 0.05

D) Addition rule of probability is that;

P(A or B) = P(A) + P(B) - P(A & B)

Applying it to this question, we have;

P(ACC or SEC) = P(ACC) + P(SEC) - P(ACC & SEC)

Plugging in the relevant values, we have;

P(ACC or SEC) = 0.5 + 0.4 - 0.05

P(ACC or SEC) = 0.85

E) from complement rule, we can find the probability that the championship game will not a have team from one of these two conferences.

Thus;

P(ACC not SEC) = 1 - P(ACC or SEC)

P(ACC not SEC) = 1 - 0.85

P(ACC not SEC) = 0.15