I have read that if a smaller number is to the left of a larger number means that the smaller number has to be subtracted from the larger number.
Ok I can understand quickly for below Roman Numbers :
IX = X - I = 10 - 1 = 9
But I have difficulty in understanding Roman Numbers that have odd Roman Numerals - say :
So if we go from Left to right we get
XIX = 10 + 1 + 10 = 21
But if we go from right to left we get
XIX = 10 + 10 - 1 = 19
So which direction we should consider before applying the rule of smaller followed by bigger Roman Numerals - left to right or right to left?