Ink Inc., a publishing firm, offers its 899 employees a cafeteria approach to benefits, in which employees can?

enroll in the benefit plan of their choice. Seven hundred thirteen employees have health insurance, 523 have dental insurance, and 489 have both health and dental insurance. (a) What is the probability p that one of the employees has either health or dental insurance? (b) What is the probability p that one of the employees has health insurance but not dental insurance?
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(a) First of all since you are finding the probability of health, or dental the events are not mutually exclusive, becuase the people who have health also have dental. It would be 730/899 + 523/899 - 489/899 = 764/899, or approx 0.85. Remember the formula for non mutually exclusive events, p(1)+p(2)-p(1, and 2). (b) Same procces here, except you just have, p(1)-p(1, and 2), the reason for this is becuase there, non mutually exclusive, but it involves both 1, and 2, becuase you are finding the probability of just health insurance. Answer = 730/899(p ofhealth)-489/899(p of health and dental)=241/899, or approx .27
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