Probability
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Classical probability |
[[$ P(A)=\dfrac{\text{number of favorable cases}}{\text{number of all cases}} $]] |
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Probability of a counter-even |
[[$ P(\bar{A}) = P(A \text{ does not occur)} = 1-P(A) $]] |
Addition rule
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When A and B are separate cases |
[[$ P(A \text{ or } B) = P(A) + P(B) $]] |
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When A and B are not separate |
[[$ P(A \text{ or } B) = P(A) + P(B) - P(A \text{ and } B)$]] |
Multiplication rule
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When A and B are independent |
[[$ P(A \text{ and } B) = P(A) \cdot P(B) $]] |
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When A and B are dependent (general multiplication rule) |
[[$P(\text{first } A \text{ and then }B) = P(A) \cdot P(B, \text{when A} \text{ has happened})$]] |