holes on a line

Hi All,
i am looking for a way to put a bunch of holes on acenterline, forexample, have them equally spaced, and have thespacing change asthe line length changes.  for example, i may have a partthat is 10" long.  want to put 4 holeson it equally, andhave the space between them change if say thelength changes to8".
any suggestions as to how to do this without having to go anddimeach point, and then crweate equations for such a beast?

Thanks
TomSolidworksParts And Features