Until s/he is reputable enough to be taken more seriously? I have answered five questions on all of SE (and this is my twentieth question). None of my answers were accepted, even though two were the only answers posted. Now, one of them got 7 upvotes, so I'm not complaining about the results, but I just want to know: should I be asking more than telling?
There's no particular reason that you should stick to one, or the other, based on your reputation. This, or stackexchange, is a questions and answers network; if you have a question to ask then you should ask (after researching it first, with Google or by searching Stack Exchange), or if you see a question you can answer, that's better than previous answers and adds new information, or explains it better than the previous answers, you should answer.
I recall from my early days on Stack Overflow it seemed difficult to garner up-votes, partly (it seemed) because I was often comparing myself to more experienced/longer-serving members with reputation in the thousands, from which I inferred that they were getting more up-votes based on their reputation and already-proven knowledge.
It does, over time, accumulate though. And once you've posted a number of answers, in the hundreds from my own recollection, it's possible for up-votes to increase due to votes on previously-written answers as well as new answers. But no: there's no specific expectation as to whether you should ask, or answer, questions at any rep level. It's a Q&A site, we need both.
Reputation shouldn't play a role when deciding whether to answer or not. The only factor worth considering is can I provide a good answer?
There is a slight bias in favour of high-reputation answerers, so you'll have a slightly harder time getting recognition for your answers in the beginning. However, most of the time, the best answer will win, no matter who wrote it.