CREATE TABLE table_27774 ("Rank by average" FLOAT, "Competition finish" FLOAT, "Couple" CLOB, "Total" FLOAT, "Number of dances" FLOAT, "Average" CLOB)

What couple averaged 21.0?
SELECT "Couple" FROM table_27774 WHERE "Average" = '21.0'
SELECT "Couple" FROM "table_27774" WHERE "Average" = '21.0'