CREATE TABLE table_8155 ("Rank" TEXT, "Nation" TEXT, "Gold" FLOAT, "Silver" FLOAT, "Bronze" FLOAT, "Total" FLOAT)

What is the sum of silver medals won for rank 7?
SELECT SUM("Silver") FROM table_8155 WHERE "Rank" = '7'
SELECT SUM("Silver") FROM "table_8155" WHERE "Rank" = '7'