Hi everyone, I am really unsure of how to do this question.

Let X have a geometric distribution with f(x) = p(1-p)^x for x = 0,1,2,....

Find the probability function of R, the remainder when X is divided by 4.

I don't know where to start, but I'm suspecting that you would construct a geometric series with r, and find an expression for f(r)... Not really sure.

Any insight would be helpful.