CREATE TABLE table_name_93 (decile INTEGER, name VARCHAR(255), gender VARCHAR(255), authority VARCHAR(255))
How many deciles have a Gender of coed, an Authority of state, and a Name of mount maunganui school?
    
SQL: SELECT SUM(decile) FROM table_name_93 WHERE gender = "coed" AND authority = "state" AND name = "mount maunganui school"