<p>If a question asks what the probability is of A or B happening, does that mean only the cases where it's just one of them, not both?</p>
<p>correct (10 chars)</p>
<p>OK, thanks.</p>
<p>Can you give a couple of examples ( with A and B: 1. mutually exclusive; 2. not mutually exclusive) to your question?</p>
<p>In rolling a pair of dice, what is the probability that the sum is 12 or at least one die shows a 2?
...the sum is 9 or at least one die shows a prime?
(The first question is from a Precalculus text book).</p>
<p>In a bag with apples and oranges, 50% of fruits are ripe, 40% are apples, and 30% are ripe apples. What is the probability of the randomly pulled out fruit to be either a ripe fruit or an apple?
(Rephrased question from the same book).</p>