CREATE TABLE table_name_10 (population_2001_census NUMBER, population_1991_census VARCHAR2)

What is the number of Population 2001 Census that has 476,815 in Population 1991 Census?
SELECT SUM(population_2001_census) FROM table_name_10 WHERE population_1991_census = 476 OFFSET 815
SELECT SUM("population_2001_census") FROM "table_name_10" WHERE "population_1991_census" = 476 OFFSET 815 ROWS