Let's say it said
(213 / 6) + 17 / 3
What this means is:
You need 3 of a particular material at particular refinement level to make your target. You currently have 17 of them. But you also have 213 of that material at a lesser refinement level, and it takes 6 of those lesser refined materials to refine to the level needed.
For example, it could mean you have 213 Beetroot Bundle (green refinement) and 17 Beetroot Sap (blue refinement). You can refine those 213 Bundles into 35 Saps, which together with your original 17 saps would give you 52 saps. And you need 3 saps to make your target, thus having enough material for 17 such targets.
Makes sense?
-- Rustyx --- 92R / 92S / 92M on Reni (Guild KnightShift). Yes, running the new FOTM R/M, cause I am not elf enough to be WD/S.
Oh, and people who have more than 3 classes are clinically insane.