ANSWER
[tex]2\colon3[/tex]EXPLANATION
We want to write the ratio of hits to innings.
This means that we want to write the numbers in the form:
[tex]a\colon b[/tex]There were 6 hits in 9 innings. Hence, the ratio of hits to innings (in simplest form) is:
[tex]\begin{gathered} 6\colon9 \\ \Rightarrow2\colon3 \end{gathered}[/tex]That is the answer.