The Work-in-Process inventory account of a manufacturing firm shows a balance of $24,000 at the end of an accounting period. The job cost sheets of two uncompleted jobs show charges of $3,500 and $5,450 for materials, and charges of $2,800 and $3,120 for direct labor. From this information, what predetermined overhead rates, as a percentage of direct labor costs, does the company appear to be using?