CREATE TABLE table_65835 ("Rank" CLOB, "Nation" CLOB, "Gold" FLOAT, "Silver" FLOAT, "Bronze" FLOAT, "Total" FLOAT)

How many Gold medals for the Nations with 6 or more Bronze medals and 18 or more Silver?
SELECT AVG("Gold") FROM table_65835 WHERE "Bronze" > '6' AND "Silver" > '18'
SELECT AVG("Gold") FROM "table_65835" WHERE "Bronze" > '6' AND "Silver" > '18'