Question

 

C  Let A and B be event of a sample space S such that P (A) = 0.4, P (B) = 0.8 and P (AnB) =0.3 Find (a) P (A/B) (b) P (B/A)

Answer 1

a)

the probability of A under the condition B:

$P (A|B)=P(A\cap B)/P(B)=0.3/0.8=3/8$

b)

the probability of B under the condition A:

$P (B|A)=P(A\cap B)/P(A)=0.3/0.4=3/4$