At year end, dub's wind generator co. had a $40,000 debit balance in its manufacturing overhead control account. overhead is applied to products based on direct labor cost. Relevant account balance information at year-end follows:
- Work in process finished goods cost of goods
- inventory inventory sold
- direct material $20,000 $80,000 $120,000
- direct labor 10,000 40,000 50,000
- factory overhead 20,000 80,000 100,000
- totals 50,000 200,000 270,000
a) what predetermined OH rate was used during the year?