We can say that this its an arithmetic sequence because it has a common difference:
d=303-309=-6
d=297-303=-6
Arithmetic sequences are represented by the following expression:
[tex]a_n=a_1+(n-1)d[/tex]Where,
an=The term we want to find
a1= first term of the sequence
n= term position
d=common difference
[tex]\begin{gathered} a_{33}=309-6(33-1) \\ a_{33}=309-192 \\ a_{33}=117_{} \end{gathered}[/tex]