CREATE TABLE festival_detail (festival_id DECIMAL, festival_name TEXT, chair_name TEXT, location TEXT, year DECIMAL, num_of_audience DECIMAL)
CREATE TABLE nomination (artwork_id DECIMAL, festival_id DECIMAL, result TEXT)
CREATE TABLE artwork (artwork_id DECIMAL, type TEXT, name TEXT)

What is the average number of audience for festivals?
SELECT AVG(num_of_audience) FROM festival_detail
SELECT AVG("num_of_audience") FROM "festival_detail"