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If P(A|B) gt P(A), then which of the fol...

If `P(A|B) gt P(A)`, then which of the following is correct:
(A) `P(B | A) lt; P(B)` (B) `P(AnnB) lt P(A)* P(B)` (c)` P(B|A) gt P(B)` (D) `P(B | A) = P(B)`

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To solve the problem, we need to analyze the condition given and derive the implications step by step. ### Step 1: Understand the Given Condition We are given that: \[ P(A|B) > P(A) \] This means that the probability of event A occurring given that event B has occurred is greater than the probability of event A occurring independently. ### Step 2: Use the Definition of Conditional Probability By the definition of conditional probability, we have: \[ P(A|B) = \frac{P(A \cap B)}{P(B)} \] Substituting this into our condition gives: \[ \frac{P(A \cap B)}{P(B)} > P(A) \] ### Step 3: Rearranging the Inequality Multiplying both sides by \( P(B) \) (assuming \( P(B) > 0 \)): \[ P(A \cap B) > P(A) \cdot P(B) \] This shows that the probability of both A and B occurring together is greater than the product of their individual probabilities. ### Step 4: Analyze the Options Now, we need to analyze the options provided: - **Option (A)**: \( P(B|A) < P(B) \) - **Option (B)**: \( P(A \cap B) < P(A) \cdot P(B) \) - **Option (C)**: \( P(B|A) > P(B) \) - **Option (D)**: \( P(B|A) = P(B) \) From our derived condition \( P(A \cap B) > P(A) \cdot P(B) \), we can conclude that option (B) is incorrect. ### Step 5: Find \( P(B|A) \) Now, let's find \( P(B|A) \): Using the definition of conditional probability: \[ P(B|A) = \frac{P(A \cap B)}{P(A)} \] Since we know \( P(A \cap B) > P(A) \cdot P(B) \), we can substitute: \[ P(B|A) = \frac{P(A \cap B)}{P(A)} > \frac{P(A) \cdot P(B)}{P(A)} = P(B) \] This shows that: \[ P(B|A) > P(B) \] Thus, option (C) is correct. ### Conclusion The correct answer is: **(C) \( P(B|A) > P(B) \)**

To solve the problem, we need to analyze the condition given and derive the implications step by step. ### Step 1: Understand the Given Condition We are given that: \[ P(A|B) > P(A) \] This means that the probability of event A occurring given that event B has occurred is greater than the probability of event A occurring independently. ### Step 2: Use the Definition of Conditional Probability ...
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