Table schema:
CREATE TABLE table_name_77 (density__per_km²_ INTEGER, rank VARCHAR, area__km²_ VARCHAR)

Question: what is the least density (per km²) when the rank is 5 and the Area (km²) is less than 125,755?
SQL: SELECT MIN(density__per_km²_) FROM table_name_77 WHERE rank = "5" AND area__km²_ < 125 OFFSET 755