Question

In Roman numerals, what happens
(i) if a symbol of smaller value is written to the right of a symbol of greater value?
(ii) if a symbol of smaller value is written to the left to the left of a symbol of greater value?
Explain with the help of examples.

Answer 1

(i) If a symbol of smaller value is written to the right of a symbol of greater value, its value gets added to the value of the greater symbol.
For example, let us take VI. Here, the value of V in decimal value = 5
And the value of I in decimal value = 1
Now, 5 > 1, the left part is greater than the right part.
So we will add the value of the smaller value of the greater one.
$\therefore$ The decimal value of VI = 5 + 1 = 6

(ii) If a symbol of smaller value is written to the left of a symbol of greater value, its value is subtracted from the value of the greater symbol.
For example, let us take IX.
Here, the decimal value X = 10
While the decimal value if I = 1
10>1, the value on the left is greater than the value on the right.
So the decimal value of IX = 10 - 1 = 9.

But we need to be a little careful while using this rule.
The symbols, V, L, and D are never written to the left of a symbol of greater value, i.e. V, L, and D are never subtracted.