Write SQL query to solve given problem: Among the cars with an engine displacement of no less than 400 cubic millimeter, how many cars cost at least 30,000?. Keep the solution inside sql tag ```sql [SQL-Query] ```
SELECT COUNT(*) FROM data AS T1 INNER JOIN price AS T2 ON T1.ID = T2.ID WHERE T1.displacement > 400 AND T2.price > 30000