What is the number of dances for the team that averages 20.6?
CREATE TABLE "averages" (
  "rank_by_average" real,
  "place" real,
  "couple" text,
  "total_points" real,
  "number_of_dances" real,
  "average" text
);
SELECT "number_of_dances" FROM "averages" WHERE "average"='20.6';