a.The first step is to calculate the estimated total overhead costs in the two departments.
Casting
Finishing
The second step is to combine the estimated manufacturing overhead costs in the two departments ($24,000 + $31,800 = $55,800)to calculate the plantwide predetermined overhead rate as follow:
The overhead applied to Job D is calculated as follows:
Overhead applied to a particular job = Predetermined overhead rate x Machine-hours incurred by the job
= $5.58 per MH x (2,700 MHs + 2,400 MHs)
= $5.58 per MH x (5,100 MHs)
= $28,458
Job D's manufacturing cost:
b.The overhead applied to Job J is calculated as follows:
Overhead applied to a particular job = Predetermined overhead rate x Machine-hours incurred by the job
= $5.58 per MH x (1,300 MHs + 3,600 MHs)
= $5.58 per MH x (4,900 MHs)
= $27,342
Job J's manufacturing cost: