csat-suneung 2014 Q23

csat-suneung · South-Korea · csat__math-B 3 marks Conditional Probability Direct Conditional Probability Computation from Definitions
Among 50 members of a marathon club who participated in a certain marathon, the number of members who completed the marathon and the number who withdrew are as follows. (Unit: persons)
CategoryMaleFemale
Completed279
Withdrew86

When one member is randomly selected from the participants and is found to be female, the probability that this member completed the marathon is $p$. Find the value of $100 p$. [3 points]
Among 50 members of a marathon club who participated in a certain marathon, the number of members who completed the marathon and the number who withdrew are as follows.\\
(Unit: persons)
\begin{center}
\begin{tabular}{ | c | c | c | }
\hline
Category & Male & Female \\
\hline
Completed & 27 & 9 \\
\hline
Withdrew & 8 & 6 \\
\hline
\end{tabular}
\end{center}
When one member is randomly selected from the participants and is found to be female, the probability that this member completed the marathon is $p$. Find the value of $100 p$. [3 points]