Compound Probability (AND / OR)
Section: Statistics & ProbabilityBank code: STA-CPRGRE frequency: HighPro
1. Core Idea
Compound events combine two or more simple events. Two connective words control everything:
- AND -> multiply. Both events happen.
- OR -> add (then subtract the overlap, if any). At least one happens.
Getting the connective right is more important than any formula in this topic.
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