CREATE TABLE table_31979 ("Rider" TEXT, "Bike" TEXT, "Laps" FLOAT, "Time" TEXT, "Grid" FLOAT)

Tell me the average Laps for grid larger than 12 and bikes of ducati 999rs for dean ellison
SELECT AVG("Laps") FROM table_31979 WHERE "Grid" > '12' AND "Bike" = 'ducati 999rs' AND "Rider" = 'dean ellison'
SELECT AVG("Laps") FROM "table_31979" WHERE "Bike" = 'ducati 999rs' AND "Grid" > '12' AND "Rider" = 'dean ellison'