Table schema:
CREATE TABLE table_name_41 (ties INTEGER, goals_for VARCHAR, goals_against VARCHAR, team VARCHAR)

Question: What is the average number of ties when goals against is less than 56 for Ottawa Hockey Club and the goals for is more than 47?
SQL: SELECT AVG(ties) FROM table_name_41 WHERE goals_against < 56 AND team = "ottawa hockey club" AND goals_for > 47