Basic Compounding Question

[beta1607]

I know how to calculate compound gains if you make periodic deposits over time into an account and you account balance started at zero dollars. Is there a way to do this if you start with a lump sum of cash and make periodic deposits over time on top of this or do you have to just calculate the two values individually and add them together?

So say you start with 30,000 and add 100/month as opposed to starting with 0 and adding 100/month.

THanks!