Question

Express the following as a Roman numeral: 99

Answer 1

Hint:
Here we will first understand the rules for converting numbers to Roman numerals. Then we will convert the required number by following those rules step by step. We will first break that number into a sum or difference of small numbers as required. Then we will convert the value of those small numbers in Roman numerals and then we will combine the whole value.

Complete step by step solution:
Let’s first understand the rules for converting numbers to Roman numerals.
There are three primary rules for converting numbers to Roman numerals:-
1) A letter can be repeated only thrice, not more than that.
2) If one or more letters are placed after another letter of greater value then we have to add that amount.
3) If one or more letters are placed before another letter of greater value then we have to subtract that amount.
Now, the question here is to convert 99 to Roman numerals.
By using the rules, we can write 99 as \[\left[ {\left( {100 - 10} \right) + \left( {10 - 1} \right)} \right]\] .
Here we will first convert \[\left( {100 - 10} \right)\] .
For \[\left( {100 - 10} \right)\] , we will follow the subtractive rule of conversion to Roman numerals .
So the value of \[\left( {100 - 10} \right)\]in Roman numerals is \[XC\] .
Now for \[\left( {10 - 1} \right)\] , we will again follow the subtractive rule of conversion to Roman numerals.
So the value of \[\left( {10 - 1} \right)\]in Roman numerals is \[IX\] .
Now using additive rule of conversion to Roman numerals in \[\left[ {\left( {100 - 10} \right) + \left( {10 - 1} \right)} \right]\]
So the value of \[\left[ {\left( {100 - 10} \right) + \left( {10 - 1} \right)} \right]\]in Roman numerals is \[XCIX\] .

The required value of \[99\] in Roman numeral is \[XCIX\].

Note:
Roman numerals are a numeral system which originated in ancient Rome. Roman numerals are the combinations of the letters \[I, V, X, L, C, D\] and \[M\] which are used in specific order for a particular value.
Roman letters are the English alphabets but not all English alphabets are used in Roman numbers only seven letters of English alphabets are used in Roman numbers which are \[I, V, X, L, C, D\] and \[M\].