How would you add up in step by step increments the numbers of 490 999 492 and 19 in Roman numerals showing how you obtained your answer?

Answer 1

Because of changes made to the rules governing the Roman numeral system during the Middle Ages today we would convert the equivalent of the above numbers into Roman numerals as CDXC, CMXCIX, CDXCII and XIX respectively which makes them almost impossible to add up.

But there is evidence to support the fact that the Romans probably wrote out these numerals in a simplified format as XD, IM, XDII and IXX respectively because:-

XD = CCCCLXXXX because 500-10 = 490

IM = DCCCCLXXXXVIIII because 1000-1 = 999

XDII = CCCCLXXXXII because 502-10 = 492

IXX = XVIIII because 20-1 = 19

Hence the addition of 490, 999, 492 and 19 in Roman numerals would work out as:-

XD+IM = IXMD (1489)

IXMD+XDII = XXMMI (1981)

XXMMI+IXX = MM (2000)

Note that if instead you were to add up these numerals in an unsimplified format the answer would be the same.

Source of research and reference: "History of Mathematics" volume 2 by David Eugene Smith first published in 1925 and ISBN 0486 204 308