CREATE TABLE table_76447 ("Rank" FLOAT, "Nation" TEXT, "Gold" FLOAT, "Silver" FLOAT, "Bronze" FLOAT, "Total" FLOAT)

Which Rank has a Nation of south korea, and a Silver larger than 0?
SELECT SUM("Rank") FROM table_76447 WHERE "Nation" = 'south korea' AND "Silver" > '0'
SELECT SUM("Rank") FROM "table_76447" WHERE "Nation" = 'south korea' AND "Silver" > '0'