As the title suggests, I am interested to know the chances of a middle-ranking journal's acceptance of a paper by an unknown author, detailing comparatively elementary results. By elementary, I mean results which are simply stated and simply proven: requiring knowledge only up to perhaps undergraduate year 3 or 4 courses. The results are new but do not have any obvious implications, nor are they usually considered as well-known interesting questions (not like open questions posed by previous authors). The "interestingness" of the results are mediocre at best. The methodology involved is new, but there is nothing to show that it is applicable in other related problems in the field, nor that it is significant in any way beyond the paper. Note that the field I am interested in is mathematics.
So, what are the chances of a journal accepting such a paper? My initial reaction is that perhaps this kind of papers would seem too trivial, given that often papers published in journals consider material from the PhD level or beyond. But then again, it is novel research with results interesting to some, so perhaps they are worth publishing.
(You can assume that the results and methodology given in the paper are truly novel and correct.)