For two events to be "mutually exclusive", it means that they cannot happen at the same time. An example is pulling a black diamond card. In a deck of cards, diamonds are red.
So the question is: "Is it possible to volunteer and meet the GPA requirements at the same time?" The answer is "Yes, because 250 applicants have done so"
This means that the two events "volunteer" and "meet GPA requirements" are not mutually exclusive. This boils things down between choice A or choice B
Now onto calculating the probability Let, A = applicant volunteers B = applicant meets GPA requirements
P(A) = 600/2000 = 0.300 P(B) = 950/2000 = 0.475 P(A and B) = 250/2000 = 0.125
Using those values, we can say.... P(A or B) = P(A) + P(B) - P(A and B) P(A or B) = 0.300 + 0.475 - 0.125 P(A or B) = 0.65 P(A or B) = 65% which is part of the answer
We got 65% so that points to choice B as the final answer
Note: another way to find P(A or B) is to note how 250 meet both requirements so 950-250 = 700 meet the GPA hurdle only, 600-250 = 350 volunteer only, so 700+350+250 = 1300 either meet one requirement or both out of 2000. So 1300/2000 = 0.65 = 65%
