user: Question: What are the average Laps on Grid 15?
Columns: ['Rider', 'Manufacturer', 'Laps', 'Time', 'Grid']
Types: ['text', 'text', 'real', 'text', 'real']
Sample row: ['Simone Corsi', 'Aprilia', 20.0, '39:59.020', 8.0]
SQL:

assistant: SELECT AVG("Laps") FROM "Table" WHERE "Grid" = 15.0;