Table schema:
CREATE TABLE table_name_85 (altitude__mslm_ INTEGER, density__inhabitants_km_2__ VARCHAR, rank VARCHAR)

Question: Which Altitude (mslm) has a Density (inhabitants/km 2) smaller than 1233, and a Rank of 9th?
SQL: SELECT SUM(altitude__mslm_) FROM table_name_85 WHERE density__inhabitants_km_2__ < 1233 AND rank = "9th"