Question

Find the joint probability of AA and BB for the following: a) P(A)=.36 and P(B|A)=.87 b) P(B)=.53 and P(A|B)=.

Answer 1

Note that
P(A∩B) = P(B|A) P(A)

Therefore
P(A∩B) = 0.87*0.36 = 0.31

Also
P(B∩A) = P(A|B) P(B)
0.31 = P(A|B)*0.53
P(A|B) = 0.31/0.53 = 0.585