The puzzle goes something like this
In the US every 13th libertarian is a pescatarian and every 11th pescatarian is a libertarian. Are there more libertarians or pescatarians?
The obvious answer seems incorrect to me, yet I don’t know how to go about solving this correctly.
$\begin{array}{ccccccccccccc} &&&&&&P&&&&&&\\&&&&&&P&&&&&&\\&&&&&&P&&&&&&\\&&&&&&P&&&&&&\\&&&&&&P&&&&&&\\ L&L&L&L&L&L&\rm both&L&L&L&L&L&L\\ &&&&&&P&&&&&&\\ &&&&&&P&&&&&&\\ &&&&&&P&&&&&&\\ &&&&&&P&&&&&&\\&&&&&&P&&&&&&\\ \end{array}$