SOLUTION: Could use some help with this please. If P( A and B)=0.40 and P(A)=0.20 what is the value of P(B|A)? What is wrong with this question? Thank you for your time

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Question 742030: Could use some help with this please.
If P( A and B)=0.40 and P(A)=0.20 what is the value of P(B|A)? What is wrong with this question?
Thank you for your time

Answer by Edwin McCravy(20065)   (Show Source): You can put this solution on YOUR website!

1. First reason why the problem is flawed:

P(B|A) =  =  =  = 2.

That's impossible because all probabilities are between 0 and 1.

2. Second reason why the problem is flawed:

P(A and B) can never be greater than P(A) or greater than P(B),

yet we are given the impossible case P(A and B)=0.40 and P(A)=0.20  

Edwin


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