Suppose the probabilities that an adult American man has hig

Suppose the probabilities that an adult American man has high blood pressure and/or high cholesterol are shown in the table: What is the probability that: a man has both conditions? a man has high blood pressure? a man with high blood pressure has high cholesterol ? a man has high blood pressure if it is known he has high cholesterol?

Solution

A.

P(man has high blood pressure and high cholestorel) = 0.21

B.

P(a man has high blood pressure) = 0.21+52 = 0.73

C.

P(a man with high blood pressure has high cholestorel) = P(a man has high blood pressure and high cholestorel)/P(a man has high blood pressure) = 0.21/0.73 = 0.29

D.

P(a man has high blood pressure given that he has high cholestorel) = P(a man has high blood pressure and high cholestorel)/P(a man has high cholestorel) = 0.21/(0.21+0.11) = 0.66