STAT 301 - Business Statistics
Lecture Review #3 - Conditional Probability

Review questions:

1) What is meant, by independent events? Dependent events?

2) What are mutually exclusive events? Are they independent or dependent?

3) What is a conditional probability?

4) Why don’t gambling "systems" work at dice games, roulette, and the lottery … while they do work at card games like blackjack?

5) Dr. Rasp argues that racial profiling is (usually) an incorrect application of conditional probability. What is the mistake?

Computational exercises:

1) Five cards are dealt, at random, from a standard 52-card deck. What is the probability that all five are of the same suit? (For poker players: this is the chance of being dealt a flush.)

2) In class, we had data on Stetson enrollments, as follows:

a) What is the probability that a Music student is male?

b) What is the probability that a male student is a music major?

c) Are gender and major independent or dependent events? Explain.

3) Circulation data indicate that 40% of the population of DeLand read the Daytona Beach News-Journal, while 15% read the DeLand Beacon — with 10% of the city reading both papers. What fraction of News-Journal readers also read the Beacon?

SOLUTIONS:
1) 0.00198
2a) 0.495     2b) 0.067
3) 0.25