Question

Canadian Blood Services says that about 46% of the Canadian population has Type O blood, 42% Type A, 9% Type B, and the rest Type AB.a. Someone volunteers to give blood. What is the probability that this donor 1. has Type AB blood? 2. has Type A or Type B? 3. is not Type O? b. If you examine one person, are the events that the person is type A and that the person is Type O disjoint or independent or neither? c. If you examine two people, are the events that the first is type A and that the second is Type O disjoint or independent or neither?

Answer 1

(a)

From the given data, the following Table is fomed:

O	0.46
A	0.42
B	0.09
AB	0.03

(1)

P(AB) = 0.03

(2)

P(A OR B) = P(A) + P(B) = 0.42 + 0.09 = 0.51

(3)
P(Not O) = 1 - 0.46 = 0.54

(b)

For one person:

Since P(A and O) = 0, the events that the person is Type A and that the person is Type O are disjoint.

Since P(A and B) P(A) P(B), the events that the person is Type A and that the person is Type O are not independent.

(c)

For two persons:

Since P(A and O) 0, the events that the first is Type A and that the second is Type O are not disjoint.

Since P(A and B) = P(A) P(B), the events that the person is Type A and that the person is Type O are independent.