All human blood can be typed as either O, A, B, or AB. The distribution of the types varies a bit with race. Choose an African American person at random. Here are the approximate probabilities that the person you choose will have blood type O, B, or AB:
?
?
$$\begin{array} { | l | l | l | l | l | }
\hline \text { Blood type } & \text { O } & \text { A } & \text { B } & \text { AB } \
\hline \text { Probability } & 0.50 & ? & 0.20 & 0.05 \
\hline
\end{array}$$ Considering having type AB blood to be an undesirable outcome, what are the odds of having type AB blood?

Question

All human blood can be typed as either O, A, B, or AB. The distribution of the types varies a bit with race. Choose an African American person at random. Here are the approximate probabilities that the person you choose will have blood type O, B, or AB:
?
?
$$\begin{array} { | l | l | l | l | l | } 
\hline \text { Blood type } & \text { O } & \text { A } & \text { B } & \text { AB } \
\hline \text { Probability } & 0.50 & ? & 0.20 & 0.05 \
\hline
\end{array}$$ Considering having type AB blood to be an undesirable outcome, what are the odds of having type AB blood?

Quizplus · Accepted Answer

The probability of having type AB blood is 0.05. The odds of having type AB blood can be found by calculating the probability of having type AB and dividing it by the probability of not having type AB. The probability of not having type AB is the sum of the probabilities of having types O, A, and B, which is 0.50 + ? + 0.20 = 0.70. So, the odds of having type AB blood are:

0.05/(1-0.70) = 0.05/0.30 = 0.1667

or approximately 1 in 6. Therefore, the answer is B) 0.053.

All Human Blood Can Be Typed as Either O, A