Answer: We have many options: 1) 15 artists, with 2 paintings per artist. 2) 10 artists, with 3 paintings per artist. 3) 6 artists, with 5 paintings per artist. 4) 5 artists, with 6 paintings per artist. 5) 3 artists, with 10 paintings per artist. 6) 2 artists, with 15 paintings per artist.
by different artists, then the number of artists must be more than 1. each artist shows more than 1 painting: >1 painting/artist
