Math
Basic rules.
Definition
Fundamental probability rules including the addition rule (for 'or' events), the multiplication rule (for 'and' events), and the complement rule. These rules form the foundation for all probability calculations.
Examples
Real-world.
- 1 P(A or B) = P(A) + P(B) − P(A and B) for any two events
- 2 P(not A) = 1 − P(A): the probability of not rolling a 6 is 1 − 1/6 = 5/6
Key Fact
P(A or B) = P(A) + P(B) − P(A∩B); P(A') = 1 − P(A)