William W. answered • 02/08/21

Math and science made easy - learn from a retired engineer

Create a two way frequency chart using the info provided. Like this:

a) To find the probability of being enrolled in either, that would be 318 + 210 but since there are 120 in both, and you can't double count, subtract 120:

(318 + 210 - 120)/500 = 408/500 = 0.816

b) There are 198 that are "Econ Enrolled" AND "Not Math Enrolled". There are 90 that are "Math Enrolled" AND "Not Econ Enrolled". 198+90 = 288 and 288/500 = 0.576

c) There are 92 not enrolled in either so 92/500 = 0.184