I know the odds on my first pull are:

10/300 = 3.33%

Second pull (provided I do not get a good prize on the first pull) are:

10/299 = 3.3445%

And so on...

Now, let's vary the mix:

What are the chances, before I do my first pull, that in using my ten tokens I will get at least one good prize, and how do I express said formula?

And, to make it really tricky, can this be done in Excel?