Roman Numerals

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Roman Numerals

• Author Matt Hampton
• CS 255
• http//ellerbruch.nmu.edu

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Where Have We Seen Roman Numerals?

• You may have seen World War 1 referred to as WWI
  and World War 2 referred to as WWII.
• The 1998 Winter Games in Nagano were known as
  XVIII Winter Games, meaning 18th Winter Games.
• Last January you may recall a special event
  occurred known as Super Bowl XXXVIII, meaning
  Super Bowl 38.

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The Basic Values of Roman Numerals

• I one (1)
• V five (5)
• X ten (10)
• L fifty (50)
• C one hundred (100)
• D five hundred (500)
• M one thousand (1,000)

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Now Lets Try Reading Numbers Using Roman Numerals

• If a smaller numeral follows AFTER a larger
  numeral, such as (12) then add the value of the
  numerals together.
• Example
• XII means 10 2 11
• If a smaller numeral comes BEFORE a larger
  numeral, such as (4) then subtract the value of
  the smaller from the value of the larger numeral.
  
• Example
• IV means 5 1 4

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Here Are Some More Examples

• XX means 10 10 20
• LV means 50 5 55
• VII means 5 2 7
• IX means 10 1 9
• LIX means 50 (10 - 1) 50 9 59
• XCIX means (100 - 10) (10 - 1)
• 90 9 99

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What is so different between Arabic and Roman
Numerals?

• The value of Roman Numerals depends on the
  placement of each numeral.
• Example IV 4 and VI 6
• The Arabic system has place values such as the
  ones place and tens place.
• Example 10 means the 1 is in the tens place and
  the 0 is in the ones place.
• Another difference is that Roman Numerals do not
  have a symbol representing zero. Instead they
  used words such as nothing.

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Sources

• Imakewebsites. Roman Numerals. 20, April 2004.
  http//www.romannumerals.co.uk
• Ask Dr. Math. 1994-2004 The Math Forum. 21, April
  2004.http//mathforum.org