CREATE TABLE table_204_922 (id DECIMAL, "rank" DECIMAL, "nation" TEXT, "gold" DECIMAL, "silver" DECIMAL, "bronze" DECIMAL, "total" DECIMAL)

how many nations won at least three silver medals ?
SELECT COUNT("nation") FROM table_204_922 WHERE "silver" >= 3
SELECT COUNT("nation") FROM "table_204_922" WHERE "silver" >= 3