CREATE TABLE "table1_27255755_1" (
  "no_in_series" real,
  "no_in_season" real,
  "title" text,
  "directed_by" text,
  "written_by" text,
  "original_air_date" text,
  "u_s_viewers_millions" text
);

Question: What is the highest series number with 9.17 million US viewers?
SQL: SELECT MAX("no_in_series") FROM "table1_27255755_1" WHERE "u_s_viewers_millions"='9.17';