Funso (Chichewa): Kodi kusiyana kwa  mitengo yapakatikati ya chimanga yokwera kwambiri ndi yotsika kwambiri ndi kotani?
Question (English): What is the average price difference between the highest and lowest maize prices?
Table: commodity_prices (difficulty: hard)
SQL: SELECT AVG(max_price - min_price) FROM (SELECT district, MAX(price) AS max_price, MIN(price) AS min_price FROM commodity_prices WHERE commodity = 'Maize' GROUP BY district);
Result: [(341.32323333200003,)]