490 is CDXC in Roman Numerals/
Explanation:
C = 100, D = 500. The rule is that a smaller number to the left of a larger one is subtracted, so the first part, CD is 500 - 100 = 400.
A smaller number to the right is added, so the second part is XC meaning 100 (C) minus 10 (X) = 90.
It was the equivalent of 490 in the times of the ancient Romans but the modern way of writing 490 in Roman numerals is now CDXC
Under today's rules 490 expressed in Roman numerals is CDXC but the Romans themselves would have probably preferred XD.
On Converting between Arabic and Roman Numbers we get: 490 in roman numerals is written as : CDXC where 400=CD XC=90.
10490 in Roman Numerals is MMMMMMMMMMCDXC.Another Possibility:(X)CDXC or XCDXC but with an horizontal bar over the first numeral X to indicate multiplication by a thousand in the same way that numerals in brackets also indicate multiplication by a thousand.
The person might have meant 490 (literally 10 before 500), but standard notation for 490 would be CDXC
It was the equivalent of 490 in the times of the ancient Romans but the modern way of writing 490 in Roman numerals is now CDXC
Under today's rules 490 expressed in Roman numerals is CDXC but the Romans themselves would have probably preferred XD.
On Converting between Arabic and Roman Numbers we get: 490 in roman numerals is written as : CDXC where 400=CD XC=90.
10490 in Roman Numerals is MMMMMMMMMMCDXC.Another Possibility:(X)CDXC or XCDXC but with an horizontal bar over the first numeral X to indicate multiplication by a thousand in the same way that numerals in brackets also indicate multiplication by a thousand.
The person might have meant 490 (literally 10 before 500), but standard notation for 490 would be CDXC
CDXC
CDXC
cdxc 400+90
Five hundred is shown as a D, so 400 is D minus 100 or C (DC). Ninety is 100 minus 10 (XC), so the answer is CDXC.
The Roman numeral CDXC represents the number 490. C (100) is subtracted from D (500) to give 400, and XC (90) is added to 400 to get 490.
Not a proper Roman numeral. D is 500. X is ten It could be 510. Or it could be in improper attempt to write 490 (which would be CDXC).
XD is not in the standard form for a Roman numeral, but I would guess its value is 490. It should be written as CDXC