XXXL is not a valid Roman numeral.
It would be 20 if that was a correct way to write in Roman Numerals
But 20 is written as XX, hence the shorter amount of numbers and needing to follow the rules on Roman numeric numbers
also such as CC = 200 or would it be 0 .. BUT..there is no zero in RN
Rules for Formation of Roman-numerals
In rules for formation of Roman-numerals system there is no symbol or digit for zero. This system has no place value system. The digit or digits of lower value is/are placed after or before the digit of higher value. The value of digits of lower value is added to or subtracted from the value of digit of higher value. Using the certain rules for formation of Roman-numerals is given below.
Rule 1: The roman digits I, X and C are repeated upto three times in succession to form the numbers.
(a) We know the value of I = 1, value of X is 10 and value of C is 100.
(b) The value of I, X and C are added as:
I = 1
II = 1 + 1 = 2
III = 1 + 1 + 1 = 3 X = 10
XX = 10 + 10 = 20
XXX = 10 + 10 +10 = 30
C = 100
CC = 100 + 100 = 200
CCC = 100 + 100 + 100 = 300
(c) No digit is repeated in succession more than thrice, i.e., I, X and C cannot be repeated more than 3 times.
(d) The digits V, L and D are not repeated. The repetition of V, L and D is invalid in the formation of numbers.
Rule 2: (a) When a digit of lower value is written to the right or after a digit of higher value, the values of all the digits are added. As:
VI = 5 + 1 = 6
VII = 5 + 1 + 1 = 7
VIII = 5 + 1 + 1 + 1 = 8
XI = 10 + 1 = 11
XII = 10 + 1 + 1 = 12 XV = 10 + 5 = 15
XVI = 10 + 5 + 1 = 16
LX = 50 + 10 = 60
LXV = 50 + 10 + 5 = 65
(b) Value of similar digits are also added as indicated in rule 1
III = 1 + 1 + 1 = 3
XXX = 10 + 10 + 10 = 30
XX = 10 + 10 = 20
Rule 3: When a digit of lower value is written to the left or before a digit of higher value, then the value of the lower digit is subtracted from the value of the digit of higher value. As:
IV = 5 - 1 = 4
IX = 10 - 1 = 9
XL = 50 - 10 = 40
XIV = 10 + (5 - 1) = 14 XIX = 10 + (10 - 1) = 19
XXIX = 10 + 10 + (10 - 1) = 29
XLV = (50 - 10) + 5 = 45
CLIX = 100 + 50 + (10 - 1) = 159
However, V is never written to the left of X.
Rule 4: (a) If we have to write the numbers beyond 10 we should write the number 10 or groups of number 10 and then number 1 or 5 as the case may be. Then these numbers are used to change to the corresponding Roman numerals. As:
12 = 10 + 2 = 1 0 + 1 + 1 = XII
20 = 10 + 10 = XX
22 = 10 + 10 +1 + 1= XXII
26 = 10 + 10 + 5 + 1 = XXVI
39 = 10 + 10 + 10 + (10 - 1) = XXXIX
37 = 10 + 10 + 10 + 5 + 1 + 1 = XXXVII
(b) According to this pattern, numbers higher than number 40 are also formed:
43 = (50 - 10) + 1 +1 + 1= XLIII
56 = 50 + 5 + 1 = LVI1
59 = 100 + 50 + (10 - 1) = CLIX
1238 = 1000 + 100 + 100 + 10 + 10 + 10 + 5 + 1 + 1 + 1 = MCCXXXVIII
Rule 5: If a horizontal line is drawn over the symbols or digits of Roman numerals, then the value of the numerals becomes 1000 times. As:
XV = 15 but XV = 15000,
CLV = 155 but CLV = 155000
For example:
(i) 13 = XIII
(ii) 14 = XIV
(iii) 18 = XVIII
(iv) 26 = XXVI
(v) 39 = XXXIX
(vi) 42 = XXXXII
(vii) 61 = LXI
(viii) 545 = DXLV
(ix) 217 = CCXVII
(i) VII = 7
(ii) XXXIV = 34
(iii) XXXVII = 37
(iv) XLIII = 43
(v) XLVIII = 48
(vi) LII = 52
(vii) CXL = 140
(viii) CXLV = 145
These are the five rules for formation of Roman-numerals system explained using examples.
check out math only math com
130
XXXl ? 31
It is: 50-30 = XX = 20
The number 222 can be represented by the Roman numeral CCXXII
The Roman numeral MCMXXV represents the number 1925.
Roman numeral MCMLXXX is the number 1980.
XXXl ? 31
It is: 50-30 = XX = 20
The number 222 can be represented by the Roman numeral CCXXII
The Roman numeral MCMXXV represents the number 1925.
The number 27 as a Roman numeral is XXVII
The Roman numeral for the number 1973 is MCMLXXIII
The roman numeral CXCIV is the number 194.
Roman numeral MCMLXXX is the number 1980.
The Roman Numeral L is equivalent to the number 50.
No Roman numeral exists for zero.
That is not a valid Roman Numeral.
It is the Roman Numeral for the number 6. It is the Roman Numeral for the number 6.