Denoting Random Numbers in Equations

Question

I'm trying to document an equation in a report that uses a random number generated between 1 and 0, is there any formal way in mathematics to document this or should i just use the letter r?

Answer 1

Traditionnally, random variables are uppercase ($X$,$Y$,...), while their values are lowercase ($x$,$y$,...).

Besides that, you will have to explicitly write that $X$ is a random variable.