For the same reasons why we need numbers today to work out weights, measures, distances, money, censuses, statistics, geometry, problem solving .... etc
to follow roman numerals is sereos in working
MDCCCLXX
In Roman numerals the letter M equals 1,000. To write 2,000 you need 2xM (2x1,000) so it is written like this MM
The number 23 in Roman numerals is XXIII. The number 00 has no equivalent in Roman numerals as the had no symbol to represent 0, they didn't need one in their system. The number 2300 in Roman numerals would be MMCCC
Arabic numerals need a nought figure to identify positional place value of numbers whereas Roman numerals does not need a nought figure because the positional place value of these numerals are self evident.
Why did society need numerals
Society needed to develop numerals so they could communicate the number of sheep or other animals or any other number of things. It probably started thousands of years ago.
to follow roman numerals is sereos in working
For exactly the same reasons why we need numerals today.
MDCCCLXX
For the purposes of identifying different weights and measures as well as needing to know the distances of the conquered countries were from Rome.
In Roman numerals the letter M equals 1,000. To write 2,000 you need 2xM (2x1,000) so it is written like this MM
The number 23 in Roman numerals is XXIII. The number 00 has no equivalent in Roman numerals as the had no symbol to represent 0, they didn't need one in their system. The number 2300 in Roman numerals would be MMCCC
Arabic numerals need a nought figure to identify positional place value of numbers whereas Roman numerals does not need a nought figure because the positional place value of these numerals are self evident.
The number "0" does not have a specific representation in Roman numerals. Roman numerals were based on a system of adding and subtracting values of different symbols, so there was no need for a symbol to represent zero.
Roman numerals are still needed nowadays because they are the numerical branch of the Latin language which is still used and spoken today.
Necessity is the mother of all inventions and Roman numerals were needed in the past just for the same reasons that we still need numbers today.