Calendars and Roman & Arabic Numerals

Calendars and Roman & Arabic Numerals

Index

General Introduction

The idea of this webpage is to dispel the urban myth that relates to when a decade, century, millennium, etc, start and end by relating this to the original calendars that utilised Roman numerals to "count" the days, months and years.

It must be remembered, and stressed, that under the counting system that utilises Roman numerals there is NO zero ("0") digit. The Romans had no concept of this "number" until they changed their counting system and adopted the Arabic numerals comprising the 0 thru 9 numering system that we use today.

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Some Useful Websites on Roman & Arabic numerals

The following websites may be useful in relation to Roman & Arabic numerals. Some are general and some relate to calendars. Return to Top

Application to Calendars

The following tables show the years, in both Roman and Arabic numerals, in which Decades, Centuries and Millennia commence and end.

Index

Decades

Arabic Numerals Roman Numerals Description
01 - 10 I - X 1st decade
11 - 20 XI - XX 2nd decade
21 - 30 XXI - XXX 3rd decade
31 - 40 XXXI - XL 4th decade
41 - 50 XLI - L 5th decade
51 - 60 LI - LX 6th decade
61 - 70 LXI - LXX 7th decade
71 - 80 LXXI - LXXX 8th decade
81 - 90 LXXXI - XC 9th decade
91 - 100 XCI - C 10th decade
Return to Application to Calendars

Centuries

Arabic Numerals Roman Numerals Description
001 - 100 I - C 1st century
101 - 200 CI - CC 2nd century
201 - 300 CCI - CCC 3rd century
301 - 400 CCCI - CD 4th century
401 - 500 CDI - D 5th century
501 - 600 DI - DC 6th century
601 - 700 DCI - DCC 7th century
701 - 800 DCCI - DCCC 8th century
801 - 900 DCCCI - CM 9th century
901 - 1000 CMI - M 10th century
Return to Application to Calendars

Millennium

Arabic Numerals Roman Numerals Description
0001 - 1000 I - M 1st millennium
1001 - 2000 MI - MM 2nd millennium
2001 - 3000 MMI - MMM 3rd millennium
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Some Real Year Ranges - Centuries and Decades

Arabic Numerals Roman Numerals Description
1801 - 1900 MDCCCI - MCM 19th century
1901 - 2000 MCMI - MM 20th century
2001 - 2100 MMI - MMC 21st century
2001 - 2010 MMI - MMX 1st decade of 21st century
2011 - 2020 MMXI - MMXX 2nd decade of 21st century
2021 - 2030 MMXXI - MMXXX 3rd decade of 21st century
2031 - 2040 MMXXXI - MMXL 4th decade of 21st century
2041 - 2050 MMXLI - MML 5th decade of 21st century
Return to Application to Calendars
URL for this homepage: http://pmyers.pcug.org.au/General/Calendars_and_Roman_&_Arabic_Numerals.htm

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