A probability is the number of desired outcomes divided by the number of total outcomes. In the first case,
[tex]\begin{gathered} \#of\text{ desired outcomes = 4} \\ \#\text{ total outcomes = 8} \end{gathered}[/tex]because there are 4 red zones from a total of 8. Then, we have
[tex]P(\text{red)}=\frac{4}{8}=\frac{1}{2}[/tex]Similarly, for the green zone, we get
[tex]P(\text{green)}=\frac{3}{8}[/tex]and for the yellow zone
[tex]P(\text{yellow)}=\frac{1}{8}[/tex]and finally, for the not yellow zone
[tex]\begin{gathered} P(\text{not yellow)=1-P(yellow)=1-}\frac{1}{8} \\ P(\text{not yellow)=}\frac{7}{8} \end{gathered}[/tex]