Write SQL query to solve given problem: List the case number of the crimes in wards with population below 52000 that have beat greater than the 90% of the average beat of all crimes.. Keep the solution inside sql tag ```sql [SQL-Query] ```
SELECT COUNT(T1.report_no) FROM Crime AS T1 INNER JOIN Ward AS T2 ON T1.ward_no = T2.ward_no WHERE T2.Population < 52000 AND T1.beat > ( SELECT AVG(T1.beat) * 0.9 FROM Crime AS T1 INNER JOIN Ward AS T2 ON T1.ward_no = T2.ward_no WHERE T2.Population < 52000 )