If A and B are two events associated with a random experiment such that P(A)=0.5,P(B)=0.3 and P(A∩B)=0.3, find P(A∪B).
We know by addition theorem on probability
P(A∪B)=P(A)+P(B)−P(A∩B)
=0.5+0.3 - 0.2
= 0.8 - 0.2 =0.6
∴P(A∪B)=0.6