We need to find the probability that a student, selected at random, is a junior.
In order to do so, we can divide the total of students that are junior to the total of students in that class.
We have:
[tex]\begin{gathered} \text{total of juniors: }2+6=8 \\ \\ \text{total of students: }4+3+6+4+2+6+2+3=30 \end{gathered}[/tex]Thus, that probability P(junior) is:
[tex]P(junior)=\frac{8}{30}\cong0.27=\frac{27}{100}=27\%[/tex]Therefore, approximately 27% of the students in that class are junior students.