Please help. I can't get the math right

Budgeted Volume Processing Hours (Cases) Per Case Tortilla chips 2,700 0. 12 Potato chips 3,900 0. 10 Pretzels 4,200 0. 15 Total 10,800 If required, round all per-case answers to the nearest cent. a. Determine the single plantwide factory overhead rate per processing hour b. Use the overhead rate in (a) to determine the amount of total and per-cas accepted accounting principles Total Per-Case Factory Overhead Factory Overhead Tortilla chips Potato chips Pretzels Tota Check My Work All work saved