Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
### Context:
CREATE TABLE table_name_73 (gold INTEGER, bronze VARCHAR, silver VARCHAR)
### Question:
How many Gold medals for the Nations with 6 or more Bronze medals and 18 or more Silver?
### Answer:
SELECT AVG(gold) FROM table_name_73 WHERE bronze > 6 AND silver > 18