Lectures - 3.1 Probability Measures: Axioms and Properties

Let A and B be subsets of U.
Pr(A’) = 0.7
Pr(A U B) = 0.6
Pr(B) = 0.4
What is Pr(A ∩ B)?

• A. 0.1
• B. 0.3
• C. 0.6

In a particular survey,
80% say they regularly shop at Walmart
60% regularly shop at Kroger
10% regularly shop at neither.
What’s the probability that a randomly selected person from the survey regularly shops at both stores?

• A. 10%
• B. 30%
• C. 50%