What average gold has China (chn) as the nation with a bronze greater than 1?
CREATE TABLE "medal_table" (
  "rank" text,
  "nation" text,
  "gold" real,
  "silver" real,
  "bronze" real,
  "total" real
);
SELECT AVG("gold") FROM "medal_table" WHERE "nation"='china (chn)' AND "bronze">1;