What did roman numerals look like and information on these?

Answer 1

I = one, V= 5, X =10, L=50, C = 100, D = 500, M=1000. 9 for example is 1 less than 10 therefore it is written IX, 11 is one more than 10= XI.

Answer 2

Roman numerals are a numeral system used in ancient Rome and are still occasionally used today for decorative purposes or in some specific contexts. The basic symbols in the Roman numeral system are I, V, X, L, C, D, and M, representing numbers 1, 5, 10, 50, 100, 500, and 1000, respectively. Roman numerals are typically written as a combination of these symbols, with certain rules for their arrangement and repetitions to form larger numbers.