CREATE TABLE "grand_tour_finishers" (
  "rider" text,
  "year" real,
  "final_position_giro" real,
  "final_position_tour" real,
  "final_position_vuelta" real
);

Question: What is the average year that has a final Tour position of 54 and a final Vuelta position over 55?
SQL: SELECT AVG("year") FROM "grand_tour_finishers" WHERE "final_position_tour"=54 AND "final_position_vuelta">55;

Question: What is the final Vuelta position associated with a final Giro position over 39 and a final Tour position of 90?
SQL: SELECT "final_position_vuelta" FROM "grand_tour_finishers" WHERE "final_position_giro">39 AND "final_position_tour"=90;

Question: How many Giro positions are associated with the year 1971 and Tour final positions over 50?
SQL: SELECT COUNT("final_position_giro") FROM "grand_tour_finishers" WHERE "year"=1971 AND "final_position_tour">50;