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If P(A) = 0.3 , P(B) = 0.4 and P(A|B) = 0.5 , then what is the value of P(B|A) ?

Options

  1. A0.325
  2. B0.333
  3. C0.375
  4. D0.667

Correct answer

D. 0.667

Step-by-step solution

Given P(A) = 0.3 , P(B) = 0.4 and P(A|B) = 0.5 . Using the formula for conditional probability: P(A|B) = P(A B) P(B) 0.5 = P(A B) 0.4 P(A B) = 0.5 0.4 = 0.2 Now, finding P(B|A) : P(B|A) = P(A B) P(A) P(B|A) = 0.2 0.3 = 2 3 0.667 Answer: 0.667

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