How many crowd sizes were recorded at the game when the home team scored 7.8 (50)?
CREATE TABLE "round_of_16" (
  "home_team" text,
  "home_team_score" text,
  "away_team" text,
  "away_team_score" text,
  "ground" text,
  "crowd" real,
  "date" text,
  "time" text
);
SELECT COUNT("crowd") FROM "round_of_16" WHERE "home_team_score"='7.8 (50)';