Roman numerals are defined in mathematics as a numeral system in which distinct letter combinations represent numbers. The most commonly used roman numbers from 1 to 10 are I, II, III, IV, V, VI, VII, VIII, IX, and X. IV represents the number four in these notations, while IX represents the number nine. In this context, IV means “one less than 5,” and IX means “one less than 10.”
Roman numerals use the base ten or decimal systems rather than place value notation. A combination of symbols will be used to represent the Arabic numeral. The Roman numbers are all derived from the English alphabet. On the other hand, Roman numerals are not utilized in all English alphabets. Modern Roman numerals use seven letters to represent various numbers. I, V, X, L, C, D, and M have integer values of 1, 5, 10, 50, 100, 500, and 1000.
Let’s discuss “XXV and XXVIII Roman Numerals” in detail with their definition, conversion, and many examples.
XXV Roman Numerals
By combining the roman numerals that have been changed, the XXV Roman Numerals can be written as numbers. The right translation of XXV Roman Numerals results from the higher roman numerals coming before the lower ones. Let’s look at how to convert XXV Roman numerals in the correct number translation.
How to Write XXV Roman Numerals?
Any of the two methods shown below can be used to calculate the numerical value of XXV Roman Numerals:
Method 1: We divide the roman numerals into single letters, write the numerical value of each letter, and then add/subtract them.
XXV = X + X + V = 10 + 10 + 5 = 25
Method 2: In this method, we consider adding and subtracting groups of roman numerals such as,
XXV = XX + V = 20 + 5 = 25
As a result, XXV roman numeral has a numerical value of 25.
XXVIII Roman Numerals
XXVIII Roman Numerals can be expressed as numbers by combining the translated roman numerals, i.e.
⇒ X + X + V + I + I + I
⇒ 10 + 10 + 5 + 1 + 1 + 1
The translation of XXVIII Roman Numerals is correct since the higher roman numerals come before the lower roman numerals. Let’s learn to convert XXVIII Roman numerals into the correct number translation.
How to Convert XXVIII Roman Numerals into its Numerical Value?
To obtain the numerical value of XXVIII Roman Numerals, use one of the two methods provided below:
Method 1: We separate the roman numerals into single letters, write the numerical value of each letter, and add/subtract them in this method.
⇒ X + X + V + I + I + I
⇒10 + 10 + 5 + 1 + 1 + 1
Method 2: In this method, we use groups of roman numerals for addition or subtraction, such as,
⇒(XX) + (VIII)
⇒20 + 8
As a result, the numerical value of XXVIII roman numerals comes out to be 28.
Basic Rules to Write Roman Numerals
Students must master the rules for writing Roman numbers to avoid mistakes. The four fundamental rules for writing Roman numerals are as follows:
- The letters I, X, and C can be repeated thrice in a row. Furthermore, the letters L, V, and D cannot be repeated; otherwise, the number is considered invalid.
- It is subtracted if a lower value digit is put to the left of a higher value number.
- It is added if a lower value digit is put to the right of a higher value digit.
- Only the letters I, X, and C can be subtractive numerals.
Rules to Convert Roman Numerals to Numbers
The following are the rules for translating roman numerals to numbers.
- A bar is placed over a number to multiply it by 1000 times.
- When a lower-valued letter is placed to the left of a higher-valued number, the smaller number is deducted from the greater one.
- When a higher-valued letter is placed to the left of a lower-valued number, the sum of both values is obtained.