The American Red Cross says that about 45% of the U. S. population has Type O blood, 40% Type A, 11% Type B, and the rest Type AB.

a) One person volunteers to give blood. What is the probability they don't have Type O blood?

b) Among four potential donors (chosen at random), what is the probability that all of them have Type A blood?

c) Among four potential donors (chosen at random), what is the probability that none of them have Type O blood?

d) Among four potential donors (chosen at random), what is the probability that at least one person has Type O blood?

a) The probability is %55

b) The probability is %0.15

c) The probability is %9.15

d) The probability is %91.85

Step-by-step explanation:

a) We need to basically subtract probability of 0 type blood from 1:

P=1-0.45=0.55

b) The probability of one person that is having A blood type is %11. Then probability of four persons that are having A blood type will be:

(0.11) ^4=0.00015

c) We need to approach to this question same as B. Probability of having not 0 type of blood is %55. Then probability of four persons that are not having 0 type of blood will be:

(0.55) ^4=0.0915

d) To find the probability we can simply subtract probability of four persons that are having 0 type blood from 1:

1-0.0915=0.9185