Question

If A and B are independent events, which equation must be true?


P(B|A) = P(A)



P(B|A) = P(B)



P(B|A) = P(A) × P(B)



P(B|A) = P(A) + P(B)

Answer 1

If two events A and B are independent, then the probability of A occurring is unaffected by whether or not B has occurred. Therefore:
P(A|B) = P(A).
You can use the same reasoning to find the correct choice of equation.

Answer 2

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