I have a list of directories:

/1-30/
/31-44/
/45-55/
/56-91/
/92-201/

How do I identify which directory is 41 being which directory has 41 in it? i.e. 31-44

Additionally, when I get into that directory, I have these files:

1000-93020.txt
93020-294384.txt
294385-399483.txt
399483-994945.txt

How do I find 94094, same concept with 94094 in between the data sets, i.e. 93020-294384.txt

What is the fatest way to do this without having to list out everything or search through everything?