If y varies inversely as x, this means there is some value k such that:
[tex]y=\frac{k}{x}[/tex]
Using the given information, we can find k:
[tex]39=\frac{k}{3}[/tex]
[tex]39*3=k[/tex]
So then k=117. Now we just need to solve for y when x=11:
[tex]y=\frac{117}{11}[/tex]