- - with these numbers - I II III IV V VI VII VIII IX X L C D M - you make the mathematical operations?

Answer 1

I know the Romans multiplied by "halving and doubling"
Take 2 numbers to multiply.
If the first number is odd add the second to the pot which will become the answer eventually.Then take one from the first number
If even do nothing. Then halve the first number and double the second.
Repeat the process until the first number becomes one, add the second to the pot and that's the answer.
Computers can use this method as it works well in binary

Answer 2

X times L = D
D times II = M
X^3 = M = II times D