CREATE TABLE table_1354805_6 (rank_by_average VARCHAR2, number_of_dances VARCHAR2)

tell the mean of the times competition for the 7 jigs
SELECT rank_by_average FROM table_1354805_6 WHERE number_of_dances = 7
SELECT "rank_by_average" FROM "table_1354805_6" WHERE "number_of_dances" = 7