Using Venn probabilities and independent events, it is found that the probability that either event a or b occurs is of 0.65 = 65%.
In a Venn probability, two events are related with each other, as are their probabilities.
The "or probability" is given by:
[tex]P(A \cup B) = P(A) + P(B) - P(A \cap B)[/tex]
If two events, A and B, are independent, we have that:
[tex]P(A \cap B) = P(A)P(B)[/tex]
In this problem, the probabilities are:
Hence:
[tex]P(A \cup B) = 0.3 + 0.5 - 0.15 = 0.65[/tex]
The probability that either event a or b occurs is of 0.65 = 65%.
You can learn more about Venn probabilities and independent events at https://brainly.com/question/14478923