Question

Based on outcomes since 1967, the probability a team from the National League wins the baseball World Series in any given year is 0.44. Based on outcomes since 1967, the probability a team from the National Football conference wins the Superbowl in any given year is 0.53. Assume whether a team from the National League wins the World Series in a year is independent of whether a team from the National Football Conference wins the Superbowl in the same year. What is the probability a team from the National League wins the World Series in a given year or a team from the National Football Conference wins the Superbowl in the same year?

Answer 1

0.7368

Explanation:

Let the occurrence that a team from the National League wins the Baseball World Series be termed EVENT A

and the occurrence that a team from the National Football Conference wins the Superbowl be termed EVENT B

We assumed that Event A and Event B are independent.

This means that the probability of Event A occurring is the same, whether or not Event B occurs, and vice versa.

P(Event A) = 0.44

P(Event B)= 0.53

P(Event A or Event B) = P(A) + P(B) - P(A and B)

The keywords here are "or" and "and".

To get P(A or B), let's find P(A and B)

P(A and B) = 0.44 × 0.53 = 0.2332

P(A or B) = 0.44 + 0.53 - 0.2332 = 0.97 - 0.2332 = 0.7368