I know that exist several packages, like
fp that allow to make all kinds of computations.
But I do not understand the correct way to use them.
I need some simple examples of multiplication and division.
I would like compute some data and output them with a custom .sty file.
An Example is:
Italy = 800 000 km of roads (by wikipedia)
SRS = 14 839.9 km (the paths of the project)
SRSpercent = SRS / Italy * 100
And I would like that
SRS as the input variables,
SRSpercent as one of the output variables.
I need this so that I do not have to rewrite the numbers in the papers every day.