The most important thing is probably a sound understanding of multiplication and division, its fairly easy to miss out a decimal place or 0 when using the flight computer for this; so if you can have a rough idea of the answer you're looking for it will reduce the chances of making an error. Alongside this, a very basic understanding of vector triangles, it helps to be able to make an educated guess at headings/ground-speeds etc. I wouldn't worry too much though, everything you need will be in the study material.
but I can't find any questions specifically maths related.
There are no
specifically maths related questions in the syllabus, it just ties into the other subjects.
Good luck with it and enjoy.