The contingency table below provides a joint frequency distribution for a random sample of patients at a hospital classified by blood type and sex. Blood Type $$\begin{array} { | l | c | c | c | c | c | }
\hline \text { Sex } & \text { O } & \text { A } & \text { B } & \text { AB } & \text { Total } \
\hline \text { F } & 96 & 95 & 25 & 9 & 225 \
\hline M & 74 & 66 & 18 & 7 & 165 \
\hline \text { Total } & 170 & 161 & 43 & 16 & 390 \
\hline
\end{array}$$ If a person is selected at random from the sample,find the probability that the person has blood type A and is female.
A)0.746
B)0.590
C)0.244
D)0.990
E)0.422

Question

The contingency table below provides a joint frequency distribution for a random sample of patients at a hospital classified by blood type and sex. Blood Type $$\begin{array} { | l | c | c | c | c | c | } 
\hline \text { Sex } & \text { O } & \text { A } & \text { B } & \text { AB } & \text { Total } \
\hline \text { F } & 96 & 95 & 25 & 9 & 225 \
\hline M & 74 & 66 & 18 & 7 & 165 \
\hline \text { Total } & 170 & 161 & 43 & 16 & 390 \
\hline
\end{array}$$ If a person is selected at random from the sample,find the probability that the person has blood type A and is female.
A)0.746
B)0.590
C)0.244
D)0.990
E)0.422

Quizplus · Accepted Answer

The probability that a randomly selected person has blood type A and is female is calculated by dividing the number of females with blood type A by the total number of people in the sample. There are 95 females with blood type A and the total sample size is 390. Thus, the probability is $95 / 390 = 0.2436$, which rounds to 0.244.

The Contingency Table Below Provides a Joint Frequency Distribution for a Random