A blood bank asserts that a person with type O blood and a negative Rh factor (Rh−) can donate blood to any person with any blood type. Their data show that 49% of people have type O blood and 15% of people have Rh− factor; 45% of people have type O or Rh− factor. Find the probability that a person has both type O blood and the Rh− factor.
The solution to the problem is as follows: P(O∪Rh−)=0.45 Additive Law of Probability P(A∪B)=P(A)+P(B)−P(AB) Therefore, P(OandRh−)=P(O)+P(Rh−)−P(O∪Rh−)=0.49+0.15−0.45=0.19 I hope my answer has come to your help. Have a nice day ahead and may God bless you always!