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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 given condition and the options provided. **Step 1: Understand the given condition.** We are given that \( P(A|B) > P(A) \). By the definition of conditional probability, we can express \( P(A|B) \) as: \[ P(A|B) = \frac{P(A \cap B)}{P(B)} \] Thus, the condition can be rewritten as: \[ \frac{P(A \cap B)}{P(B)} > P(A) \] **Step 2: Rearranging the inequality.** Multiplying both sides by \( P(B) \) (assuming \( P(B) > 0 \)): \[ P(A \cap B) > P(A) \cdot P(B) \] This means that the probability of both events A and B occurring together is greater than the product of their individual probabilities. **Step 3: Analyze the options.** Now, let’s analyze each option given in the question: - **(A)** \( P(B|A) < P(B) \) - **(B)** \( P(A \cap B) < P(A) \cdot P(B) \) - **(C)** \( P(B|A) > P(B) \) - **(D)** \( P(B|A) = P(B) \) From our earlier result \( P(A \cap B) > P(A) \cdot P(B) \), we can conclude that option (B) is incorrect because it contradicts our finding. **Step 4: Find \( P(B|A) \).** Now, we can find \( P(B|A) \): \[ P(B|A) = \frac{P(A \cap B)}{P(A)} \] Since we know \( P(A \cap B) > P(A) \cdot P(B) \), we can substitute: \[ P(B|A) = \frac{P(A \cap B)}{P(A)} > \frac{P(A) \cdot P(B)}{P(A)} = P(B) \] Thus, \( P(B|A) > P(B) \), which means option (C) is correct. **Final Conclusion:** The correct answer is (C) \( P(B|A) > P(B) \). ---

To solve the problem, we need to analyze the given condition and the options provided. **Step 1: Understand the given condition.** We are given that \( P(A|B) > P(A) \). By the definition of conditional probability, we can express \( P(A|B) \) as: \[ P(A|B) = \frac{P(A \cap B)}{P(B)} \] Thus, the condition can be rewritten as: ...
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