The probability of contamination in batch 1 of a drug (event A) is 0.16, and the probability of contamination in batch 2 of the drug (event B) is 0.09.

Question

The probability of contamination in batch 2, given that there was a contamination in batch 1, is 0.12. Given this information, which statement is true?

A. 

Events A and B are independent because P(B|A) = P(A).

B. 

Events A and B are independent because P(A|B) ≠ P(A).

C. 

Events A and B are not independent because P(B|A) ≠ P(B).

D. 

Events A and B are not independent because P(A|B) = P(A).

Answer 1

Events A and B are independent only if P(B|A) = P(B). If P(B|A) not equal P(B) then A and B are not independent.