Chapter 8.7, Problem 78PE

To determine

To calculate: Whether a person is less likely or more likely to have $\text{Rh}$ factor, if the blood type of an individual is classified according to the presence of certain antigens, substances that cause the immune system to produce antibodies. These antigens are denoted by A, B, and Rh. If an individual’s blood contains either the A or B antigens, these letters are listed in the blood type. If neither A nor B is present, then the letter O is used. If the Rh antigens is present, the blood is said to be Rh positive ${\text{Rh}}^{+}$; otherwise, the blood is Rh negative ${\text{Rh}}^{-}$. Under this system, a person with ${\text{AB}}^{+}$ blood has all three antigens, and group ${\text{O}}^{-}$ is absent all three antigens.

The distribution of blood types for people is,

${\text{O}}^{+}$	0.374
${\text{O}}^{-}$	0.066
${\text{A}}^{+}$	0.357
${\text{A}}^{-}$	0.063
${\text{B}}^{+}$	0.085
${\text{B}}^{-}$	0.015
${\text{AB}}^{+}$	0.034
${\text{AB}}^{-}$	0.006