What are the roman numerals MCD?

Answer 1

In Roman Numerals, M = 1,000; D = 500; and C = 100. Since they did not have a number for the "in between" numbers, like 400 or 200, you would use the next highest number (like 500) and subtract however much you need to get it to the number you want... like 400, you would have to subtract 100 from the 500. When you put them in order as MCD, you read them as 1,000 + (500-100) which equals 1,400. Putting the C on the left side of the D tells you to subtract 100 from 500. This is the same reason that X = 10, but IX = (10-1) or 9. Just the opposite is true, if you put the I or 1 on the other side, you would ADD it. Therefore, XI = 11.