# Check that the Roman numerals are valid. Convert and write them as Hindu-Arabic numbers. Turn numbers written using the Roman numeral system letters into numbers written in ordinary digits. Explanations

## The latest Roman numerals validated and converted to Hindu-Arabic numbers

 Is the Roman numeral MCDXLCCVDCCCI valid or not? Is it equal to 2,436 when written as a Hindu-Arabic number? Feb 01 03:51 UTC (GMT) Is the Roman numeral (C)(D)MMLXVIII valid or not? Is it equal to 402,068 when written as a Hindu-Arabic number? Feb 01 03:51 UTC (GMT) Is the Roman numeral XIXXVII valid or not? Is it equal to 36 when written as a Hindu-Arabic number? Feb 01 03:51 UTC (GMT) Is the Roman numeral MDCCCXXXXI valid or not? Is it equal to 1,841 when written as a Hindu-Arabic number? Feb 01 03:51 UTC (GMT) Is the Roman numeral IM valid or not? Is it equal to 999 when written as a Hindu-Arabic number? Feb 01 03:51 UTC (GMT) Is the Roman numeral VMCCXI valid or not? Is it equal to 1,206 when written as a Hindu-Arabic number? Feb 01 03:51 UTC (GMT) Is the Roman numeral (X)M(X)DCCCLXXVI valid or not? Is it equal to 19,876 when written as a Hindu-Arabic number? Feb 01 03:51 UTC (GMT) Is the Roman numeral (C)(M)(V)MCCCLI valid or not? Is it equal to 906,351 when written as a Hindu-Arabic number? Feb 01 03:51 UTC (GMT) Is the Roman numeral CXLIILXXXI valid or not? Is it equal to 221 when written as a Hindu-Arabic number? Feb 01 03:50 UTC (GMT) Is the Roman numeral MDLXXVIMCDXXXVII valid or not? Is it equal to 3,011 when written as a Hindu-Arabic number? Feb 01 03:50 UTC (GMT) Is the Roman numeral (C)(C)(C)(X)(C)XXIX valid or not? Is it equal to 390,029 when written as a Hindu-Arabic number? Feb 01 03:50 UTC (GMT) Is the Roman numeral MCDLXVIMDCXCIV valid or not? Is it equal to 3,158 when written as a Hindu-Arabic number? Feb 01 03:50 UTC (GMT) Is the Roman numeral CCXXL valid or not? Is it equal to 250 when written as a Hindu-Arabic number? Feb 01 03:50 UTC (GMT) All the Roman numerals validated and converted to Hindu-Arabic numbers

## The set of basic symbols of the Roman system of writing numerals

• ### (*) M = 1,000,000 or |M| = 1,000,000 (one million); see below why we prefer this notation: (M) = 1,000,000.

(*) These numbers were written with an overline (a bar above) or between two vertical lines. Instead, we prefer to write these larger numerals between brackets, ie: "(" and ")", because:

• 1) when compared to the overline - it is easier for the computer users to add brackets around a letter than to add the overline to it and
• 2) when compared to the vertical lines - it avoids any possible confusion between the vertical line "|" and the Roman numeral "I" (1).

(*) An overline (a bar over the symbol), two vertical lines or two brackets around the symbol indicate "1,000 times". See below...

Logic of the numerals written between brackets, ie: (L) = 50,000; the rule is that the initial numeral, in our case, L, was multiplied by 1,000: L = 50 => (L) = 50 × 1,000 = 50,000. Simple.

(*) At the beginning Romans did not use numbers larger than 3,999; as a result they had no symbols in their system for these larger numbers, they were added on later and for them various different notations were used, not necessarily the ones we've just seen above.

Thus, initially, the largest number that could be written using Roman numerals was:

• MMMCMXCIX = 3,999.