Question

Suppose P(A) =0.9, P(B) = 0.6, and P(B|A) = 0.2. What is P(A|B)

A) 0.36
B)0.45
C)0.3
D)0.6

Answer 1

P(B|A): P(A and B) / P(A)

P(A and B): P(A)•P(B) so 0.9 • 0.6 = 0.54

P(A|B): 0.54 / 0.9 = 0.6

Answer: D) 0.6