Question
P(A) = 0.2 P(B) = 0.2 P(A and B) = 0.04 P(B|A) = ?
Answer
$$ P(B~|~A) = 0.2 $$
Explanation
To find $ P(B~|~A) $ we use multiplication rule:
$$ \color{blue}{P(B ~|~ A) = \frac{ P(A \text{ and } B)}{P(A)}} $$In this example we have:
$$ \begin{aligned} P(B ~|~ A) &= \frac{ P(A \text{ and } B)}{P(A)} \\ P(B ~|~ A) &= \frac{ 0.04 }{ 0.2 } \\ P(B ~|~ A) &= 0.2 \end{aligned}$$This page was created using
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