If I use "modern numerals" you then get 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, ↊ and ↋. Thus twelve itself represented in this way would be… you guessed it "10". The cool thing with twelve is that it's easily divisible by lots of other numbers (1, 2, 3, 4, and 6). This makes fractions like ½, ⅓, ¼ easier and cleaner than in base ten.