How many Crowd that has a Date on saturday, 29 january and an Away team of collingwood?
CREATE TABLE "group_b" (
  "home_team" text,
  "home_team_score" text,
  "away_team" text,
  "away_team_score" text,
  "ground" text,
  "crowd" real,
  "date" text
);
SELECT AVG("crowd") FROM "group_b" WHERE "date"='saturday, 29 january' AND "away_team"='collingwood';