We Tutor All Subjects & Grade Levels - In Home And Online
November 15, 2022

Roman Numbers - Rules, Chart | What Are Roman Numbers?

When you think about numbers currently, the first of all that springs to mind is the decimal method we use daily. This system, however, is not the only approach to portray numericals. There are multiple methods utilized by different cultures worldwide that use all sorts of symbols. Classified among many one of the approach is Roman numbers.

Given that ancient Rome, Roman numerals have been a way of expressing numericals using a blend of letters from the Latin alphabet. It remained across the Middle Ages and the modern day, to the extend it is still taught in school, that is perhaps why you have come across this article.

Now, we are gonna to walkthrough Roman numbers, what they are, how they work, and how to transform Roman numerals to regular numbers.

What Are Roman Numerals?

Primarily, let's check a quick look at the history of Roman numerals. Roman numericals were first used by the historic Romans, as you may have predicted from the name. They were used in multiple aspects of the Roman world, including trade, architecture, and even war.

Presently, its extensive use is mainly due to artistic reasons. You may have seen Roman numbers as hour marks on a clock, page numbering, chapter numbers, copyright dates, or in film sequels (e.g., The Godfather Part II).

The Roman numeral approach consist of numericals using a combination of letters from the Latin alphabet. Letters are blended to create groups that represent numericals. Seven alphabets, I, V, X, L, C, D, and M, symbolizes the numericals 1, 5, 10, 50, 100, 500, and 1000, respectively. You can then mix these numbers to portray any value in the numerical system.

Meaning of the Roman numerals

Although the decimal system is based on the concept of place value, Roman numerals are founded on cumulative and subtractive principles. This means that a Roman numeral's numeric values are based on the sum of the values of its individual parts. Another key difference is that the decimal approach is founded on the number 10. In comparison, Roman numerals are based on the numericals 1 (I), 5 (V) and 10 (X).

Examples

Let's look at a few interactive examples of Roman numerals.

The electronic game street fighter IV was released in arcades as early as 2008. If we take a look at the numericals in the name, we see it includes a V in it. This is because the number 5 in Roman numerals is represented by the letter V. Preceded by it is an I, or 1. Therefore, we comprehend that this is the 4th to enter in the series utilizing the characteristics we will discuss subsequently in the article.

The movie Star Wars Episode VI was the latest entry in the original trilogy. Observing the value described, it includes a V ensued by an I. Therefore, we will include a 1 to the value of V, which is 5, comprehending this Star Wars movie is the 6th to enter the franchise.

Roman Numerals Chart

To read Roman numbers, it is important to comprehend the numeric value of all the letters. To guide make this process easy, here is a chart with every Latin characters with assigned numeric values.

 Decimal Number Roman Numeral 1 I 2 II 3 III 4 IV 5 V 6 VI 7 VII 8 VIII 9 IX 10 X 11 XI 12 XII 13 XIII 14 XIV 15 XV 16 XVI 17 XVII 18 XVIII 19 XIX 20 XX 21 XXI 22 XXII 23 XXIII 24 XXIV 25 XXV 26 XXVI 27 XXVII 28 XXVIII 29 XXIX 30 XXX 31 XXXI 32 XXXII 33 XXXIII 34 XXXIV 35 XXXV 36 XXXVI 37 XXXVII 38 XXXVIII 39 XXXIX 40 XL 41 XLI 42 XLII 43 XLIII 44 XLIV 45 XLV 46 XLVI 47 XLVII 48 XLVIII 49 XLIX 50 L 51 LI 52 LII 53 LIII 54 LIV 55 LV 56 LVI 57 LVII 58 LVIII 59 LIX 60 LX 61 LXI 62 LXII 63 LXIII 64 LXIV 65 LXV 66 LXVI 67 LXVII 68 LXVIII 69 LXIX 70 LXX 71 LXXI 72 LXXII 73 LXXIII 74 LXXIV 75 LXXV 76 LXXVI 77 LXXVII 78 LXXVIII 79 LXXIX 80 LXXX 81 LXXXI 82 LXXXII 83 LXXXIII 84 LXXXIV 85 LXXXV 86 LXXXVI 87 LXXXVII 88 LXXXVIII 89 LXXXIX 90 XC 91 XCI 92 XCII 93 XCIII 94 XCIV 95 XCV 96 XCVI 97 XCVII 98 XCVIII 99 XCIX 100 C 200 CC 300 CCC 400 CD 500 D 600 DC 700 DCC 800 DCCC 900 CM 1000 M

How to Convert from Roman Numbers to Decimal Numbers

Since we have the handy table of Roman numbers, we can use that data to change numericals back and forth simply. Following these steps, you will transform these values whenever you want.

Steps to Convert Roman numerals to Regular Numbers

To change Roman numbers to decimal numericals, we will use the linear and subtractive principles we discussed.

• Begin with the leftmost Roman numeral in the group.

• If the Roman number to its right is smaller in value, then add the both values.

• If the Roman numerical to its right is greater in value, deduct the Roman numeral on the right from the Roman numbers to its left.

• All you must do now is replicate this method unless you reach the end of the Roman number group.

Let's check out how you can change Roman numbers with a some examples.

Example 1

Consider the Roman numeral LXXVI.

• Begin with the leftmost Roman number, that is L or 50.

• The Roman numeral to its right is X or 10. Considering 10 is less than 50, we sum the both values and get 60.

• The Roman number to the right of X is X again. We sum 10 to 60 and the result is 70.

• The Roman numeral to the right of X is V or 5. Because 5 is less than 70, we sum the two values and the result is 75.

• The Roman numeral to the right of V is I or 1. Since 1 is less than 75, we sum the both values and the result is 76.

We cease here at the end of the Roman number group. Consequently, the Roman number LXXVI is as same as the decimal number 76.

Example 2

Take into account the Roman numeral MCMIII.

• Start at the leftmost Roman number, that is M or 1000.

• The Roman numeral to its right is C or 100. Since 100 is less than 1000, and it is followed by an M, this value means 900.

• The Roman number to the right of M is I or 1. Since 1 is less than 1900, we sum the both values and get 1901.

• The Roman number to the right of I is I again. We sum 1 to 1901 and we find 1902.

• The Roman numeral to the right of I is I again. We sum 1 to 1902 and get 1903.

Since we have arrived the end of the Roman numeral group, we halt here with our result. Thus, the Roman number MCMIII is equal to the decimal number 1903.

With this data and a little practice, you will transform Roman numerals to regular numbers like a pro!