Orcish Mathematics

Orcish Mathematics is a vigesimal system of mathematics used by orcs and half-orc. Ogres and ogrekin use similar systems.

Numbers

Orcs use a vigesimal, or base-20, system. They only use the natural numbers (not including zero).

Naming Conventions

In orcish, numbers are referred to as "digits." Groups of five are "limbs," and groups of twenty are "pots," referring to how four limbs would be in a pot while cooking a victim. Because of inconsistencies with how many digits orcs and their prey (humanoid or otherwise) have on each limb or in total, these terms are colloquially used as approximates, such as "limb" referring to groups of 4–6 or "pot" referring to groups of 16–24.
In some big enough tribes, the term "feast" was developed to mean 20 "pots" or around 400. However, for most orcs, such large numbers aren't often needed or end up being incredibly imprecise.
Half-orcs or non-cannibalistic orcs still use these terms either in ignorance or tolerance of their violent origin.

Symbols

Orcs usually use tally marks to notate "digits" and a box to refer to a "pot." Some also employ horizontal lines to refer to a "limb." A square inside of a square can be used for a "feast," but orcs that are smart enough to use such large numbers usually switch to other notation systems.

• 1 = I
• 2 = II
• 3 = III
• 4 = IIII
• 5 = IIII or —
• 6 = IIII I or — I
• 7 = IIII II or — II
• 8 = IIII III or — III
• 9 = IIII IIII or — IIII
• 10 = IIII IIII or ——
• 20 =
• 30 = IIII IIII or ——
• 40 =
• 50 = IIII IIII or ——
• 100 =