for d in [0-9][0-9][0-9]
do
  ( cd "$d" && your-command-here )
done

find . -maxdepth 1 -type d \( ! -name . \) -exec bash -c "cd '{}' && pwd" \;

find ~/Music/ -type d \( ! -name . \) -exec bash -c "cd \"{}\" && fdupes -dN . " \;