Answer:
320
Explanation:
To know what were the sales, after 13 years, we need to replace t nu 13 on the original equation, so
[tex]\begin{gathered} S(t)=170+50\log_3(2t+1) \\ S(13)=170+50\log_3(2(13)+1) \\ S(13)=170+50\log_3(26+1) \\ S(13)=170+50\log_3(27) \\ S(13)=170+50(3) \\ S(13)=170+150 \\ S(13)=320 \end{gathered}[/tex]
Therefore, the approximate sales after 13 years were 320 thousand units.
