First of all, the predetermined overhead will be calculated.
Predetermined overhead rate = Estimated manufacturing overhead / Estimated direct labor hour
Predetermined overhead rate = $ 258,000 ÷ 15,000 hours = $ 17.20 per direct labor hour
Actual manufacturing overheads = $ 253,000
Applied manufacturing overheads = Predetermined overhead rate × Actual direct labor hours
Applied manufacturing overheads = $ 17.20 × 13,100 = 225,320
Applied manufacturing overheads are less than actual manufacturing overheads, thus overheads are under applied.
Actual manufacturing overheads - Applied manufacturing overheads = $ 27,680 under applied