How is the drawing of lots (Qur'a) managed if the debt corresponds to a specific fraction of the slaves' value?

Primary text

If the debt equals one-third of the slaves' value, three slips are written: one for the debt and two for the estate. If the debt equals one-fourth, four slips are written: one for the debt and three for the estate. The drawing then proceeds among those whose slips represent the estate portions for manumission.