How many people attended the game that resulted in an away team score of 18.17 (125)?
CREATE TABLE "round_4" (
  "home_team" text,
  "home_team_score" text,
  "away_team" text,
  "away_team_score" text,
  "venue" text,
  "crowd" real,
  "date" text
);
SELECT SUM("crowd") FROM "round_4" WHERE "away_team_score"='18.17 (125)';