math
posted by Anonymous .
On the last math quiz, there were four A's, two B's, five C's, and one D's. If the math quizzes were returned to the students in random order, what is the probability that the first quiz returned to a student was an A or a B?

There are 12 grades total. To find the probability of A OR B, you would add the amount of A and B grades together. amt. of A's 4 amt. of B's 2.
2+4=6
probability of an A or B is 6/12 or 1/2