Redfern Audio produces audio equipment including headphones. At the Campus Facility, it produces two wireless models, Standard and Enhanced, which differ both in the materials and components used and in the labor skill required. Data for the Campus Plant for the third quarter follow.

Standard Enhanced Total

Units produced $28,2009,40037,600$

Machine$-$hours $16,92011,28028,200$

Direct labor$-$hours $21,15021,15042,300$

Direct materials costs $ $564,000$ $ $846,000$ $ $1,410,000$

Direct labor costs $338,400719,1001,057,500$

Manufacturing overhead $778,320$

Total costs $ $3,245,820$

Required:

Compute the predetermined overhead rate assuming that Redfern Audio uses direct labor costs to allocate overhead costs.