CREATE TABLE table_77257 ("Rider" TEXT, "Manufacturer" TEXT, "Laps" FLOAT, "Time/Retired" TEXT, "Grid" FLOAT)

What is the average number of laps with an accident time/retired, aprilia manufacturer and a grid of 27?
SELECT AVG("Laps") FROM table_77257 WHERE "Time/Retired" = 'accident' AND "Manufacturer" = 'aprilia' AND "Grid" = '27'
SELECT AVG("Laps") FROM "table_77257" WHERE "Grid" = '27' AND "Manufacturer" = 'aprilia' AND "Time/Retired" = 'accident'