Changes

== Subtraction ==

== Subtraction ==

Letters are put in order from greatest to least.  A lesser letter occurring before a greater letter is subtraction. When subtracting, only subtracting powers of ten such as I, X, or C is allowed. For example, subtracting a V is not allowed. Also, only one digit can be subtracted. For example, IIX is not 8 but rather use VIII for 8. Finally, one letter cannot be subtracted from another letter if it is ten times greater than it, so one would not be able to subtract X from M since M is one hundred times greater than X. Yet, X can be subtracted from either L or C, as XL (40) or XC (90). In Roman times, while any combination of numerals, which totals as the appropriate number, was considered sufficient, only the above method was considered proper. In rare cases, the number 9 is written as VIIII, rather than IX.

Letters are put in order from greatest to least.  A lesser letter occurring before a greater letter is subtraction. When subtracting, only subtracting a power of ten such as I, X, or C is allowed. For example, subtracting a V is not allowed, because VX could be more simply written as just V, and LC is the same as just L. Also, only one digit can be subtracted. For example, IIX is not 8 but rather use VIII for 8. Finally, one letter cannot be subtracted from another letter if it is ten times greater than it, so one would not be able to subtract X from M since M is one hundred times greater than X. Yet, X can be subtracted from either L or C, as XL (40) or XC (90). In Roman times, while any combination of numerals, which totals as the appropriate number, was considered sufficient, only the above method was considered proper. In rare cases, the number 9 is written as VIIII, rather than IX.

:* Example 1983 = MCMLXXXIII

:* Example 1983 = MCMLXXXIII