Can you help me solve this general accounting question using the correct accounting procedures?

Trenton Manufacturing produces steel and plastic components. In preparing the current budget, Trenton's management estimated a total of $450,000 in manufacturing overhead costs and 15,000 machine hours for the coming year. In December, Trenton's accountants reported actual manufacturing overhead incurred of $660,000 and 12,000 machine hours used during the year. Trenton applies overhead based on machine hours. What was Trenton's predetermined overhead rate for the year