Stephanie Co. uses a job order costing system. The company's executives estimated that direct labor would be $4,000,000 (400,000 hours at $10/hour) and that factory overhead would be $2,500,000 for the current period. At the end of the period, the records show that there had been 390,624 hours of direct labor and $2,200,000 of actual overhead costs. Using direct labor hours as a base, what was the predetermined overhead rate?