XXI Roman Numerals

XXI in Roman Numerals can be written in numbers by combining the value of each Roman numeral, i.e., XXI = XX + I = 20 + 1 = 21. The higher Roman numerals precede the lower numerals resulting in the correct translation of XXI Roman Numerals. In this article, let us learn how to convert Roman numeral XXI into numbers and understand the value of XXI number in English.

XXI Meaning

The meaning of XXI in English in the numerical form can be expressed as 21 using the following method.

• XXI = XX + I
• XXI = 20 + 1
• XXI = 21

How to Write XXI Roman Numerals?

XXI in Numbers

The value of XXI in numbers can be found using the following methods.

XXI in Roman Numerals Translation

The numerical value of XXI Roman Numerals can be obtained by using any of the two methods given below:

Method 1: In this method, we break the Roman numerals into single letters, write the numerical value of each letter and add/subtract them.

• XXI = X + X + I = 10 + 10 + 1 = 21

Method 2: In this method, we consider the groups of Roman numerals for addition or subtraction such as,

• XXI = XX + I = 20 + 1 = 21

Therefore, the numerical value of XXI Roman numerals is 21.

☛ Also Check: Roman Numerals Calculator

What are the Basic Rules to Write Roman Numerals?

• When a bigger letter precedes a smaller letter, the letters are added. For example: CX, C > X, so CX = C + X = 100 + 10 = 110
• When a smaller letter precedes a bigger letter, the letters are subtracted. For example: IV, I < V, so IV = V - I = 5 - 1 = 4
• When a letter is repeated 2 or 3 times, they get added. For example: MM = M + M = 1000 + 1000 = 2000
• The same letter cannot be used more than three times in succession.

Numbers Related to XXI Roman Numerals

Roman numerals were used in ancient Rome and utilized combinations of letters using the Latin alphabets I, V, X, L, C, D, and M. It may seem different than numbers, but they are similar. For example, XXI Roman numerals are equivalent to the number 21. The roman numerals related to XXI are given below:

• XX = 20
• XXI = 20 + 1 = 21
• XXII = 20 + 2 = 22
• XXIII = 20 + 3 = 23
• XXIV = 20 + 4 = 24
• XXV = 20 + 5 = 25
• XXVI = 20 + 6 = 26
• XXVII = 20 + 7 = 27
• XXVIII = 20 + 8 = 28
• XXIX = 20 + 9 = 29

FAQs on XXI Roman Numerals

What is XXI in Roman Numerals?

We will write XXI Roman numerals in the expanded form to determine its value. XXI = X + X + I = 10 + 10 + 1 = 21. Hence, the value of Roman Numerals XXI is 21.

Why is 21 Written in Roman Numerals as XXI?

We know that in Roman numerals, we write 1 as I, and 10 as X. Therefore, 21 in Roman numerals is written as XXI = XX + I = 20 + 1 = XXI.

What is the Remainder when XXI is Divided by XVIII?

We know that XXI = 21 and XVIII = 18 in numbers. On dividing 21 by 18, we get the quotient as 1 and it leaves a remainder of 3. Now, 3 = III. Therefore, when XXI is divided by XVIII, the remainder is III.

How is XXI Roman Numerals Written in Numbers?

To convert XXI Roman Numerals to numbers, the conversion involves breaking the Roman numerals on the basis of place values (ones, tens, hundreds, thousands), like this:

• Tens = 20 = XX
• Ones = 1 = I
• Number = 21 = XXI

What Should be Added to XXI Roman Number to Get MMMCMLXXXVIII?

First, we will write MMMCMLXXXVIII and XXI in numbers, i.e., XXI = 21 and MMMCMLXXXVIII = 3988. Now, 3988 - 21 = 3967. And, 3967 = MMMCMLXVII. Therefore, MMMCMLXVII should be added to 21 Roman numerals to get MMMCMLXXXVIII.

What is XXI in Hindu Arabic Numerals?

The value of XXI in Hindu Arabic numerals can be calculated using the following steps.

• We break the Roman numerals into single letters, write the numerical value of each letter and add or subtract them, as the case may be.
• In this case, XXI Roman number = X + X + I = 10 + 10 + 1 = 21
• Therefore, the value of XXI in Hindu Arabic numerals is 21.