CREATE TABLE table_64477 ("Date" FLOAT, "Doubles ,  I Class" FLOAT, "Doubles ,  II Class" FLOAT, "Greater Doubles" FLOAT, "Doubles" FLOAT, "Semidoubles" FLOAT, "Total" FLOAT)

Which Greater Doubles have Doubles, II Class smaller than 17?
SELECT AVG("Greater Doubles") FROM table_64477 WHERE "Doubles, II Class" < '17'
SELECT AVG("Greater Doubles") FROM "table_64477" WHERE "Doubles, II Class" < '17'