Blood types can be classified as either Rh+ or Rh-
88% of the Chinese population has Rh+ blood.
Let A = the event that a Chinese person has Rh+ blood.
Let B = the event that a Chinese person has Rh- blood.

1. What is the probability that two randomly selected Chinese people both have Rh+ blood? Show work.

P(all A) = P(A)P(A) = (0.88)(0.88) = 0.7744

2. What is the probability that neither of two randomly selected Chinese people have Rh+ blood? Show work.

P(none A) = P(all B) = P(B)P(B) = (0.12)(0.12) = 0.0144

3. What is the probability that at least one of two randomly selected Chinese people have Rh+ blood? Show work.

P( at least one A) = 1 - P(all notA) = 1 - (0.12)^2 = 0.9856

4. What is the probability that exactly one of two randomly selected Chinese people have Rh+ blood?
Indicate the sample space of blood types using a tree diagram to help answer the question.

AA
AB
BA
BB

P(exactly one A) = 2P(A)P(B) = 2*(0.88)(0.12) = 0.2112

5. Indicate the sample space of blood type combinations for three selected Chinese people.

AAA
AAB
ABA
ABB
BAA
BAB
BBA
BBB

6. What is the probability that exactly one of the three has Rh+ blood? Show work.

P(exactly one A) = 3*(0.88)*(0.12)^2 = 0.0380

7. What is the probability that at least one of the three has Rh+ blood? Show work.

P(at least one A) = 1 - P(all not A) = 1 - (.12)^3 = 0.9983

8. What is the probability that all three have the same blood type? Show work.

P(all A OR allB) = (0.88)^3 + (0.12)^3 = 0.6832