Acheson corporation, which applies manufacturing overhead on the basis of machine-hours, has provided the following data for its most recent year of operations. estimated manufacturing overhead $ 157,750 estimated machine-hours 4,640 actual manufacturing overhead $ 157,400 actual machine-hours 4,860 the estimates of the manufacturing overhead and of machine-hours were made at the beginning of the year for the purpose of computing the company's predetermined overhead rate for the year. the predetermined overhead rate is: