I have a Word file formatted to 6x9 page size. When I save as PDF on my Mac, the page size becomes 8.5x11. I don't see any way to control this. I've tried this with different page sizes, e.g. 5x7, and all come out 8.5x11 in the PDF.

When I use Word on my PC, the 6x9 file writes to 6x9 in the PDF!

What am I missing?