Roman Numerals

Roman Numerals

    Here are the properties that apply to Roman Numerals.
1. Additive Property
    If A symbol of greater value comes before a symbol of lesser value, add.
    Ex.
The Symbol I,X,C, and M can be repeated at most three times.
 III = 1+1+1=3
XXX = 10+10+10=30
CCC = 100+100+100=300
MMM = 1,000+1,000+1,000=3,000
2.Subtractive Property
   If a symbol lesser value comes before a symbol of greater value, subtract.
   Ex.
   IV = 5-1 = 4
   IX = 10-1 = 9
   XL = 50-10 = 40
   XC = 100-10 = 90
   CD = 500-100 = 400
   CM = 1,000-100= 900
I is used only before and after V and X. It can also be used after all other symbols. V,L and D are not used before symbols of greater value.
3.Multiplicative Property
   When a horizontal bar is written above a symbol. the value of the symbol is multiplied by 1,000.
   Ex.
__
V  = 5 x 1,000= 5,000
__
IX = 9 x 1,000 = 9,000
More bars over a symbol or symbols show larger numbers.


= 5 x 1,000 x 1,000 x 1,000 = 5,000,000




= 5 x 1,000 x 1,000 x 1,000 =5,000,000,000




Note: A horizontal bar above a symbol is called Vinculum