What are the average scores of participants with 9.226 in evening gown 
CREATE TABLE "final_competition_score" (
  "country" text,
  "preliminary" text,
  "interview" text,
  "swimsuit" text,
  "evening_gown" text,
  "average" text
);
SELECT "average" FROM "final_competition_score" WHERE "evening_gown"='9.226';