Conditional Probability and Independence (VCE SSCE Mathematical Methods): Quizzes

Pr of $A$ given $B$ has occurred

Two coin tosses

$\frac{\text{Pr}(A \cap B)}{\text{Pr}(B)}$

$\text{Pr}(A \cap B)=\text{Pr}(A|B)\text{Pr}(B)$

Multiply probabilities along the branches

$\text{Pr}(A)=\text{Pr}(A|B)\text{Pr}(B)+\text{Pr}(A|B')\text{Pr}(B')$

Can calculate directly without formula

$\text{Pr}(A \cap B)=\text{Pr}(A)\times\text{Pr}(B)$

$0.28$

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