What does XIIX mean in Roman numerals?
In Hebrew the word 'chai' ('חי') means life.
In the Hebrew numeral system ח is 10 and י is 8. So חי is
18.
This means that in the Jewish faith, the number 18 is always
linked with life.
In Roman times, Jewish people would inscribe XIIX in significant
or religious places as a blessing. They would write in Roman
numerals because Judaism was often outlawed and they had to hide
it.
Below is Mark's explanation of the Roman numeral system:
I is equivalent to 1,
V is equivalent to 5,
X is equivalent to 10,
L is equivalent to 50,
let's stop at there.
I is one, II is two, III is three, IV is four, V is 5.
The reason IV would be four instead IIII being four it means 5 -
1. Similarly, IX is 9. However, VI and XI mean 6 and 11
respectively. if a smaller number comes before a bigger number, it
is subtracted from the bigger number. Otherwise, the numbers are
added. there may be XL to represent 40 but never XXL to represent
thirty. similarly, you will never see IIV or IIX.
This is correct relating to modern use of Roman numerals. The
antique Romans did occasionally use XIIX as 18. See the tombstone
of Marcus Caelius. The second line of the inscription is "o Leg
XIIX Ann LIII s", meaning "first order of the 18th legion in his
53rd and half year".