A general concept. Primarily used in Conditional Probability Combining probabilities of 2 or more events can be done very simply but done differently between Independent and Dependent events
Consult Independent and Dependent for more info on how to find the probability of compound events.
Independent Example with weird terminology.
pg 334, question 4c asks the question: A patient takes 2 tests. One has 95% success, other has 89% What is the probability success of if at least one event occurs.
They take both tests, so, you can construct a tree diagram.
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doesn’t matter which order you take the drugs. I did 95% drug first.
the probability is, probability A + Probability B given A failed.
so, this is: 0.95 + 0.05(0.89) = 99.45