At the beginning of the year, manufacturing overhead for the year was estimated to be $670,530. At the end of the year, actual direct labor-hours for the year were 29,400 hours, the actual manufacturing overhead for the year was $665300 and manufacturing overhead for the year was under-applied by $27550. If the predetermined overhead rate is ,based on direct labor-hours, then the estimated direct labor-hours at the beginning of the year used in the predetermined overhead rate must have been: