Pls solve with good explanation

Pls solve with good explanation 16 If A, . C are three events associated with a random experiment, p(AuBuC) = -P (B C) + P(AnB n C)

Let us represent the probabilities of event A, B and C by Venn digrams. 

So in this case, to find P(A∪B∪C) we add all the probabilities and subtract the intersection between all two events and add the the intersection of all the three events together. I hope you understand the image of the venn diagram representing the union of the probabilities.