If $P(A)= 0.4, P(B) = 0.8$ and $P(A|B) = 0.6$, then $P(A∪B)$ is:
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → 0.72
$P(A)=0.4,P(B)=0.8,P(A|B)=0.6$
$P(A|B)=\frac{P(A∩B)}{P(B)}$
$⇒P(A∩B)=\frac{6}{10}×\frac{8}{10}=0.48$
$∴P(A∪B)=P(A)+P(B)-P(A∩B)$
$=0.4+0.8-0.48$
$=0.72$