Roman Numerals: Difference between revisions
71/2 is changed to 7 1/2
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=== Fractions === | === Fractions === | ||
The base "Roman fraction" is S, indicating 1⁄2. The use of S (as in VIIS to indicate | The base "Roman fraction" is S, indicating 1⁄2. The use of S (as in VIIS to indicate 7 1⁄2) is attested in some ancient inscriptions, but while Roman numerals for whole numbers are decimal S does not correspond to 5⁄10, as one might expect, but 6⁄12. This is because Roman Numeral system for numbers less than 0 are duodecimal in base (base-12). | ||
The Romans used a duodecimal rather than a decimal system for fractions, as the divisibility of twelve (12 = 22 × 3) makes it easier to handle the common fractions of 1⁄3 and 1⁄4 than does a system based on ten (10 = 2 × 5). | The Romans used a duodecimal rather than a decimal system for fractions, as the divisibility of twelve (12 = 22 × 3) makes it easier to handle the common fractions of 1⁄3 and 1⁄4 than does a system based on ten (10 = 2 × 5). | ||