LXXXIX is eighty nine. I'm not sure if there is a way to represent a half or not.
Improved Answer:
In today's modern conversion it's LXXXIXS but the Romans themselves would have probably calculated 89 and a 1/2 on a abacus counting device as LXXXVIIIIS and then wrote it out as SXC (-10.5+100 = 89.5)
Evidence of converting 89 and a 1/2 into Roman numerals as SXC can be found in the book "History of Mathematics volume II" by David Eugene Smith first published in 1925.
The problem of wrongly converting Hindu-Arabic numerals into Roman numerals arises from the fact that today's rules governing the Roman numeral system were introduced during the Middle Ages and that was centuries after the demise of the Roman Empire.
Roman numerals: M=1000, D=500, C=100, L=50, X=10, V=5, I=1 and S=1/2
There is no direct representation for the number 89.5 in Roman numerals, as Roman numerals are primarily used for whole numbers. However, 89 can be represented as LXXXIX. To indicate a half, it is common to use a dot or a line above the numeral, so 89.5 would be written as LXXXIẊ or LXXXIX̄.
89 in Roman numerals is written LXXXIX
In today's notation of Roman numerals 89 = LXXXIX
89 written in roman numerals is LXXXIX.
10/11/89 in Roman numerals is X - xi - lxxxix
The date of birth 8 28 89 in Roman numerals is VIII XXVIII LXXXIX.
89 in Roman numerals is written LXXXIX
In today's notation of Roman numerals 89 = LXXXIX
10/11/89 in Roman numerals is X - xi - lxxxix
89 written in roman numerals is LXXXIX.
The date 28-07-89 can be written in Roman numerals as XXVIII.VII.LXXXIX or you could write 28-07-1989 as XXVIII.VIII.MCMLXXXIX
The date of birth 8 28 89 in Roman numerals is VIII XXVIII LXXXIX.
The date 06-12-89 in Roman numerals is VI.XII.LXXXIX and the longer version 06-12-1989 is VI.XII.MCMLXXXIX
II/XXIV/MCMLXXXIX
XII-XXVI-LXXXIX
They are: MDCCCLXV and MDCLXXXVII respectively
Half of 1004 in Roman numerals are: DII = 502
1.5 = IS in Roman numerals because 1= I and 0.5 = S