If P (A) = 0.4, P (B) = 0.8, P (B/A) = 0.6. Find P (A/B) and P (A ∪ B).
We have, P (A ∪ B) = P (A)+ P (B)- P (A ∩ B)
From equation, 
= 
P (B ∩ A) = 
× P (A) = 0.6× 0.4
= 0.24
Hence, 
= 
= 
= 0.3 (answer)
And P (A ∪ B) = P (A)+ P (B)- P (A ∩ B)
= 0.4+0.8-0.24
= 0.96 (answer)
4