Roman Numerals
The ancient numbers that are still being used, we all have definitely seen them, let's learn them properly now.
What Are Roman Numerals?
Roman numerals system originated from ancient Rome where they used some of the Latin letters to represent numbers and used them for daily transactions, counting, and so on. The letters used in Roman numerals are I, V, X, L, C, D, and M.
How To Write Numbers With Roman Numerals?
As mentioned before, Roman numerals are made of the Latin letters I, V, X, L, C, D, and M. Each letter represents a number. Let's have a look at the following table:
Symbol | Meaning |
---|---|
I | 1 |
V | 5 |
X | 10 |
L | 50 |
C | 100 |
D | 500 |
M | 1000 |
We can put the symbols in descending order from left to right and add the numbers together. If we add all of the numbers, their sum equals the represented number. For example:
XXV = 10+10+5 = 25
XXXVII is 10 + 10 + 10 + 5 + 1 + 1 = 37
Please note that no Roman numeral can be repeated more than 3 times in a number. For example:
❌We cannot say: XXXX = 40
If we put the number with a smaller value on the left and then put the number with the greater value in front, the represented number will be the result of subtraction of the smaller symbol from the larger symbol:
XC = 100 - 10 = 90
IX = 10 - 1 = 9
Remember that only I, X, and C can be used as subtractive numerals.
When a smaller Roman numeral is between two bigger ones, we should subtract it from the number on its right side. For instance:
XIV = 10 + (5 - 1) = 14
XIX = 10 + (10 - 1) = 19
To multiply a number by a factor of 1000 a bar is located on top of it. Also, we should know that the number 'zero' has no representative letters in Roman numerals.
Let's have a look at the following table to see some Roman numbers:
Number | Roman Letter |
---|---|
1 | I |
2 | II |
3 | III |
4 | IV |
5 | V |
6 | VI |
7 | VII |
8 | VIII |
9 | IX |
10 | X |
20 | XX |
30 | XXX |
40 | XL |
50 | L |
60 | LX |
70 | LXX |
80 | LXXX |
90 | XC |
100 | C |
200 | CC |
300 | CCC |
400 | CD |
500 | D |
600 | DC |
700 | DCC |
800 | DCCC |
900 | CM |
1000 | M |
5000 | V̅ |
10000 | X̅ |