Subtraction Pattern for Roman Numerals
Date: 9/7/95 at 21:30:42 From: Anonymous Subject: Roman Numeral Rules Several of my friends and I have gotten into a friendly argument concerning the rules for Roman Numerals that I think you might be able to help us with. The question is, given that 4 is 'IV' and 9 is 'IX' and 900 is 'CM', does the subtraction pattern follow for two numerals more than two 'levels' apart, and can numerals which represent numbers starting with 5 be subtracted? For example, would 99 be 'IC', would 450 be 'LD', and would 995 be 'VM'? This came up because of a trivia question someone posed about what the year 1995 *should* be in Roman Numerals. He had hazarded the extremely simple 'MVM'. Is he right? -'f
Date: 9/8/95 at 11:28:13 From: Doctor Ken Subject: Re: Roman Numeral Rules Hello! As neat as this system would be, the normal way that people write numbers like 995 is not to use the subtraction principle over more than one level. So for instance, 995 would be CM (for 900) XC (for 90) V(for 5), making CMXCV. That's one reason they seem kind of awkward to us. -Doctor Ken, The Geometry Forum
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