Because they were used in Ancient India. The Arabs learned them from here and spread to the world. That's why in the beginning the Europeans called them Arabic numbers but the arabians itself called them Hindu numbers. So now they are jointly called the Hindu-Arabic numbers.
They are actually called Hindu-Arabic numerals, so named because the system originated in India and was brought to Europe by the Western Arabs.
448 already IS in Hindi-Arabic numerals
192 already IS in Hindi-Arabic numerals.
84 already is written in Hindi-Arabic numerals. If you want it converted to Roman numerals, it's LXXXIV
27 already is written in Hindi-Arabic numerals. (The Hindi-Arabic numerals are 0 1 2 3 4 5 6 7 8 and 9)
It is: 40
It is: XVI = 16
Exactly as in the question
X = 10
The given numerals are an invalid arrangement of Roman numerals and so therefore no equivalent Hindu-Arabic numerals are possible.
Arabic numerals are called that because the European interpretation of those numbers comes from the Arabs. The numerals are called Arabic numerals (even though they do not resemble modern Arabic numerals in the slightest) to distinguish them from Roman numerals.
The Hindu Arabic number system was in fact started by Indians, back then known as Brahmi Numerals. They then slowly evolved to become Hindu Arabic numerals.
The string "DD" is not valid so there can be no answer.
In today's terms they represent 1445
12629 is already written in Hindu/Arabic numerals, those are the numbers which are used in most countries on the planet.
12629 is already written in Hindu-Arabic numerals, which is the number system used in most countries in the world today.
The Roman numeral MMCDLXX represents the number 2470
Hindu/Arabic numbers are the system of numbers which are used in most countries of the world. 192 is a Hindu/Arabic number.