Firs, notice that we have to choose a 13 year old student at random. According to the table, we have 10 students that are 13 years old. Then, from those 10 students, 5 prefer ice skating, then, we have the following:
[tex]\begin{gathered} P(a\text{ student prefers ice skating given that the student is 13 years old)=} \\ \frac{5}{10}=\frac{1}{2}=0.5 \end{gathered}[/tex]
