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Question
If P (A) = \[\frac{7}{13}\], P (B) = \[\frac{9}{13}\] and P (A ∩ B) = \[\frac{4}{13}\], find P (A/B).
Solution
\[\text{ Given } : \]
\[P\left( A \right) = \frac{7}{13}\]
\[P\left( B \right) = \frac{9}{13} \]
\[P\left( A \cap B \right) = \frac{4}{13}\]
\[\text{ Now } , \]
\[P\left( \frac{A}{B} \right) = \frac{P\left( A \cap B \right)}{P\left( B \right)}\]
\[ \Rightarrow P\left( \frac{A}{B} \right) = \frac{\frac{4}{13}}{\frac{9}{13}} = \frac{4}{9}\]
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