XIII Roman Numeral: What Number Is XIII?
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XIII is 13 (thirteen). It is one X and three Is, all added: 10 + 1 + 1 + 1 = 13.
Reading XIII letter by letter
XIII splits by place into X (ten) and III (three).
| Letter | Value | Step | Total |
|---|---|---|---|
| X | 10 | start | 10 |
| I | 1 | add | 11 |
| I | 1 | add | 12 |
| I | 1 | add | 13 |
Why XIII is valid
- Three Is in a row
- Exactly the limit; a fourth I would be invalid.
Easy to confuse with XIII
| Typed | Problem | Reads as |
|---|---|---|
| XIIII | I can appear at most three times in a row. | XIV (14) |
| IXII | Letters are out of order: values must go from largest to smallest. | XI (11) |
XIII in names, titles and systems
- ReignLouis XIIIKing of France1610–1643Wikipedia
- Super BowlSuper Bowl XIIIJanuary 21, 1979MiamiPittsburgh Steelers beat Dallas Cowboys 35–31Wikipedia
- TitleFinal Fantasy XIII2009Wikipedia
- OlympicsGames of the XIII Olympiad1944cancelledWikipedia
- Roman legionLegio XIII Gemina49 BCWikipedia
- SystemFactor XIII, the fibrin-stabilizing factor, was the last clotting factor to receive a Roman numeral, in 1963Wikipedia
13 in Roman numerals · Roman numeral rules
