Write SQL query to solve given problem: What percent of the non volcanic islands in the Lesser Antilles group of islands have an area of no more than 300 square kilometers?. Keep the solution inside sql tag ```sql [SQL-Query] ```
SELECT SUM(CASE WHEN Area <= 300 THEN 1 ELSE 0 END) * 100 / COUNT(*) FROM island WHERE Islands = 'Lesser Antilles' AND (Type != 'volcanic' OR Type IS NULL)