How to use roman numerals<br>Understand the concept of roman numerals. Roman numerals use fewer symbols than the number system you are used to. I is the number 1 (one), v is 5 (five), and x is 10 (ten), for example.
Roman numerals is the most common number system. 
It's not,. 
( z1 system :mod ( z2 number ) :domain ( z3 numerals :mod ( z4 numerals :mod ( z5 country :name ( z6 name :op "Roman" :op "Empire" ) ) ) ) :ARG1-of ( z7 have-degree :ARG2 ( z8 common ) :ARG3 ( z9 most ) ) )