I'm going to read that as $10 profit in both cases.
If you have one domain you have the advantage that you can spend more time monitoring it and working out how to improve it. On the other hand, if it starts to lose traffic because its niche becomes less popular or you acquire a better resourced competitor, you lose a much higher percentage of your income.
On balance, I think I'd prefer the safety net of having 10 domains.
I know it isn't one of the options, but I'd like to have 3 domains earning $3.33 each. That way I have some insurance against one domain going under and leaving me with nothing while still having some ability to improve the portfolio without spreading myself too thin.