XX is 20 in Roman numerals
20 = XX
you write 71 as LXXl and 20 as XX
To write 20 in Roman numerals, you would use XX. To write 30, you would use XXX. Therefore, to write 20-30 in Roman numerals, you would write XX-XXX.
XX
XX.VI.MCMLXXVI
II.XX.MMI
I-XX-MMIX
It is: I-XX-MMI
Xii-12 xx-20 mcmxc-1990
X-XX-MMIII
83 = LXXXIII or as XXCIII (103-20)
V-XX-MMX