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_93 (roll INTEGER, authority VARCHAR, decile VARCHAR)
### Question:
What is the average roll of a school with state authority and a decile of 9?
### Answer:
SELECT AVG(roll) FROM table_name_93 WHERE authority = "state" AND decile = 9