Interesting Math History 


Question : 
What is the origin of Roman Numerals and how actually is the counting done on this system ? 
Answer : 
Roman Numerals originated in Rome and were used by the ancient Romans almost 2000 years ago. They were originally independent
symbols. In this system seven symbols
are used :
I V X L C D M 
Where I = 1, V = 5, X = 10, L = 50, C = 100, D = 500 and M = 1000.
The numbers represented are 1, 5 and multiples of 5 and 10, the number of fingers on the hand and on two hands. There is no
zero in this system. The other numerals like 2, 3, 6 are represented with these above symbols by placing them in a row and
adding or subtracting, such as :
1 = I 
6 = VI (V + I) 
2 = II 
7 = VII (V + I + I) 
3 = III 
8 = VIII (V + I + I + I) 
4 = IV (one subtracted from five) 
9 = IX (one subtracted from ten) 
5 = V 
10 = X 
19 = XIX; 27 = XXVII; 152 = CLII and so on. 
Roman numerals were used by bankers and bookkeepers until the eighteenth century as they did not trust symbols like 6, 8,
or 9 that could easily be changed to other numbers.

