A question of numbers (one for the maths fans)

That's the wrong question.We invent mathematical entities. Thus we can invent infinity. The mathematical sense of "exist" is different from the physical sense of "exist". If we can invent a suitable concept of infinity that does not cause any inconsistencies in our mathematics, then we can say that infinity exists in the mathematical sense.

Remember Zeno? He proved that you can't cross a room. In fact he proved you couldn't move at all. Understand Zeno's paradox first. Everybody knew he was wrong but no one knew how to prove it until the calculus. I may be wrong about this but I don't know of any proofs before that. Well they can. There are all kinds of series and some are very weird.
Note that there are series, and then the sum of a series..999... is a number, it's not a series. We did at various points in the explication say it was equivalent to the sum of the series .9+.09+.009... which it is. It was a way of explaining why this is true: .999... = 1.If you take some math classes, which I think would be fun, you will find math uses very precise definitions except where it can't. Like a point and a line, even number have to be understood but from there on you can precisely difine what you mean. Part of your confusions in this thread was because you confused terms. Once you get the terms sorted out it will be clearer.lfen

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To me, if .999... can equal 1, then there is a limit to how many recurring 9's you can have

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That's exactly wrong. 0.999... = 1 because there is no limit to the number of '9's after the decimal place. That is how it works.For any finite number of '9's 1 - 0.999...9 = 0.000...1
For an infinite number of '9's 1 - 0.999... = 0.000...Because it's infinite there's no point to stop and put a '1'.
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I don't think I really confused terms. I did not know of a lot of these things before this thread. Like my last post, I know I am speaking of many different things, but I am not confused about the terms, I think I got it.I really did a lot of reading on this one, but it's kind of hard to learn calculus over the internet in a couple days. Like if you go to wikipedias definition of recurring decimals, the page is full of links to help define what it is. There is actually a similar discussion there as well.I had some problems when studying it, as I didn't understand some of the symbols used in the equations. One symbol looked like a funny looking E, what does that mean?

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One symbol looked like a funny looking E, what does that mean?

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I think what you are referring to is a capital sigma (Greek).
(Mathematcs also uses a backwards 'E' for "there exists").The sigma stands for "sum". In the wikipedia discussion there's an example with 'k = 0' below it and the 'infinity' symbol (like an '8' on it's side - above). What it means is "what you would get get if you worked out the formula for k = 0, k = 1, k = 2,... on to infinity and added all the results together".Since you can't actually do that you have to use other mathematics to work out what the result would be, More precisely what you work out is the limit of the sum as k tends to infinity (i.e. where it's going as you add on the results for higher and higher values of k - but it usually won't reach that value if you stop at any finite number of results)