CREATE TABLE table_50716 ("Rank" FLOAT, "Nation" CLOB, "Gold" FLOAT, "Silver" FLOAT, "Bronze" FLOAT, "Total" FLOAT)

what is the average silver when the total is more than 20?
SELECT AVG("Silver") FROM table_50716 WHERE "Total" > '20'
SELECT AVG("Silver") FROM "table_50716" WHERE "Total" > '20'