For the Japanese title サプリ that had 11 episodes, what is the average ratings?
CREATE TABLE "2006_summer_season" (
  "japanese_title" text,
  "romaji_title" text,
  "tv_station" text,
  "episodes" real,
  "average_ratings" text
);
SELECT "average_ratings" FROM "2006_summer_season" WHERE "episodes"=11 AND "japanese_title"='サプリ';