Question: How many of these apartments have 3 bedrooms?
SQL: SELECT count ( * )  FROM Apartments WHERE apt_number IN  ( SELECT DISTINCT T2.apt_number FROM Apartment_Bookings AS T1 JOIN Apartments AS T2 ON T1.apt_id   =   T2.apt_id WHERE T1.booking_status_code   =   "Confirmed" )  AND bedroom_count  =  3