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3.7: Chapter 3 Formula Review

  • Page ID
    5544
  • 3.1 Terminology

    A and B are events

    \(P(S) = 1\) where \(S\) is the sample space

    \(0 ≤ P(A) ≤ 1\)

    \(P(A | B)=\frac{P(A \cap B)}{P(B)}\)

    3.2 Independent and Mutually Exclusive Events

    \(\text {If } A \text { and } B \text { are independent, } P(A \cap B)=P(A) P(B), P(A | B)=P(A) \text { and } P(B | A)=P(B)\)

    \(\text {If } A \text { and } B \text { are mutually exclusive, } P(A \cup B)=P(A)+P(B) \text { and } P(A \cap B)=0\)

    3.3 Two Basic Rules of Probability

    The multiplication rule: \(P(A \cap B) = P(A|B)P(B)\)

    The addition rule: \(P(A \cup B) = P(A) + P(B) - P(A \cap B)\)