One way to characterize the difference between compounding and discounting is to say that

Bridge building company estimates that it will incur $1,200,000 in overhead costs for the year. additionally, the company estimates 50,000 direct labor hours will be spent building custom walking bridges for the year at a total direct labor cost of $600,000. what is the predetermined overhead rate for bridge building company if direct labor costs are to be used as an allocation base?