Which probability rule is primarily applied when considering multiple events happening simultaneously?

The General Addition Rule is utilized when evaluating the probability of the union of two or more events, particularly when those events may not be mutually exclusive. This means that the rule accounts for the possibility that some of the events can occur simultaneously. The formula for the General Addition Rule incorporates the probabilities of the individual events and subtracts the probability of their intersection, thus ensuring that any overlapping probabilities are only counted once.

For example, if you are interested in determining the probability that either event A or event B occurs, the General Addition Rule calculates this by adding the probabilities of A and B, and then subtracting the probability that both A and B occur at the same time. This approach is essential when events can overlap, providing a more accurate measure of their combined likelihood.

In contrast, other options like the Special Addition Rule only apply to mutually exclusive events, while the Multiplicative Rules pertain to determining the probability of independent events occurring together. Permutations deal with the arrangement of items rather than probability, further emphasizing the applicability of the General Addition Rule in situations involving multiple simultaneous events.