Solution
The total number of marbles
[tex]11+22+12=45\text{ marbles}[/tex]Probability is
[tex]Probability=\frac{Possible\text{ outcome}}{Total\text{ sample space}}[/tex]Probability of red
[tex]\frac{22}{45}[/tex]Probability of green
[tex]\frac{11}{45}[/tex]Finally
P(red or green)
[tex]\begin{gathered} =\frac{22}{45}+\frac{11}{45} \\ \\ =\frac{33}{45} \end{gathered}[/tex]