b Suppose that 42 of the population have type A blood and th

b) Suppose that 42% of the population have type A blood and that 26% of the population are Caucasians who have type A blood. Find the probability that a randomly selected person is Caucasian or has type A blood.

Solution

Prob(type A blood) = 0.42

Prob(Caucasian) = 0.26

type A blood and Caucasian are independent events

prob(person is both caucasiaon and has type A blood) = Prob(type A blood) X Prob(Caucasian)

=0.42X 0.26

=0.1092

prob(person is both caucasiaon or has type A blood) = Prob(type A blood)+ Prob(Caucasian) - Prob(type A blood) X Prob(Caucasian)

=0.42+0.26-0.1092

=0.5708