I was visiting Korea (강원도 춘천시) recently and needed to ask directions to a building on a college campus. (강원대학교 for those who are interested). I was on foot and I did not immediately see a campus map anywhere, so I decided to ask someone who was walking by where to find the building.
As could be expected, most of the people on the college campus were in their early to mid-twenties. I (being in my early 30s) am likely older than most of them. However, there were a few individuals on campus for whom it was impossible to determine an exact age. The were dressed semi-formally and could have been a young professor. Maybe they were older than me, maybe they were younger.
Because I did not know how to address these people of ambiguous age, I opted to just use wait for a person that was definitely younger than me and ask them where to go.
However, this made me ponder on how I might address someone I did not know (and hence whose name I did not know) on the street if they looked to be roughly my same age. Using a term like "선생님" seems a bit too formal; using a term like "아저씨" feels a bit to demeaning.
How can I address someone who looks to be around my age when I need to speak to them once on the street for information and will likely never know their name?