Using Venn probabilities, it is found that the probability that either event occurs (a or b) is: 1.
In a Venn probability, two non-independent events are related with each other, as are their probabilities.
The "or probability" is given by:
P(A or B) = P(A) + P(B) - P(A and B)
In this problem, we have that the probabilities are given as follows:
Hence the probability that either occurs is:
P(A or B) = P(A) + P(B) - P(A and B) = 0.6 + 0.4 - 0 = 1.
More can be learned about Venn probabilities at https://brainly.com/question/25698611
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