1. General Probability Rules
Section 6.3

2. Union
In any collection of events, at least one of the events occur

3. General Addition Rule for Unions of Two Events
P(A or B) = P(A) + P(B) – P(A and B)
P(A U B) = P(A) + P(B) – P(A n B)

4. Joint Event Simultaneous occurrence of two events
The probability of a joint event is called joint probability

5. General Multiplication Rule
The probability that both of two events A and B happen together can be found by P(A and B) = P(A)P(B|A) Here P(B|A) is the conditional probability that B occurs given the information that A occurs.

6. Conditional Probability
Gives the probability of one event under the condition that we know another event.
P(A|B)

7. Definition of Conditional Probability
When P(A) > 0, the conditional probability of B given A is
P(B|A) = P(A and B)/P(A)

8. Intersection
The intersection of any collection of events is the event that all of the events occur

9. Independent Events
Two events A and B that both have positive probability are independent if P(B|A) = P(B)

10. Practice Problems
pg. 379 #