Looking at https://en.wikipedia.org/wiki/Roman_numerals https://en.wikipedia.org/wiki/Roman_numerals that abacus makes lot more sense. It was not base 10 system

Looking at https://en.wikipedia.org/wiki/Roman_numerals https://en.wikipedia.org/wiki/Roman_numerals that abacus makes lot more sense. It was not base 10 system, but bi-quinary (https://en.wikipedia.org/wiki/Bi-quinary_coded_decimal https://en.wikipedia.org/wiki/Bi-quinary_coded_decimal). For larger numbers very messy number, but one must think of how V is 5, L 50 and D 500. So they did not really have place value system. Or at least logical leap from abacus to place value. Instead they had 1, 5, 10, 50, 100, 500, 1000 and summed or deducted these. Sometimes in stylistic ways.