The use of Roman numerals continued long after the decline of the
The original pattern for Roman numerals used the symbols I, V. and X (1, 5, and 10) as simple tally marks. Each marker for 1 (I) added a unit value up to 5 (V), and was then added to (V) to make the numbers from 6 to 9:
The numerals for 4 (IIII) and 9 (VIIII) proved problematic (among other things, they are easily confused with III and VIII), and are generally replaced with IV (one less than 5) and IX (one less than 10). This feature of Roman numerals is called
The numbers from 1 to 10 (including subtractive notation for 4 and 9) are expressed in Roman numerals as follows:
The system being basically decimal, tens and hundreds follow the same pattern:
Thus 10 to 100 (counting in tens, with X taking the place of I, L taking the place of V and C taking the place of X):
Note that 40 (XL) and 90 (XC) follow the same subtractive pattern as 4 and 9.
Similarly, 100 to 1000 (counting in hundreds):
Many numbers include hundreds, units and tens. The Roman numeral system being basically decimal, each "place" is added separately, in descending sequence from left to right, as with "arabic" numbers. For example, the number 39 is XXXIX, (three tens and a ten less one), 246 is CCXLVI (two hundreds, a fifty less ten, a five and a one. As each place has its own notation there is no need for place keeping zeros, so "missing places" can be simply omitted: thus 207, for instance, is written CCVII (two hundreds, a five and two ones) and 1066 becomes MLXVI (a thousand, a fifty and a ten, a five and a one)
Roman numerals for large numbers are nowadays seen mainly in the form of year numbers (other uses are detailed later in this article), as in these examples:
The "standard" forms described above reflect typical modern usage rather than a universally accepted convention. Usage in ancient Rome varied greatly and remained inconsistent in medieval and modern times.