A theater complex is currently showing four R-rated movies, three PG-13 movies, two PG movies, and one G movie. The following table gives the number of people at the first showing of each movie on a certain Saturday:
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Suppose that one of these people is randomly selected.
a. What is the probability that the selected individual saw a PG movie?
b. What is the probability that the selected individual saw a PG or a PG-13 movie?
c. What is the probability that the selected individual did not see an R movie?