TB MC Qu. 10-208 (Algo) The Maxit Corporation has a standard costing system... The Maxit Corporation has a standard costing system in which variable manufacturing overhead is assigned to production on the basis of standard machine-hours. The following data are available for July: Actual variable manufacturing overhead cost incurred: $24,380 Actual machine-hours worked: 2,400 hours Variable overhead rate variance: $4,620 U Total variable overhead spending variance: $6,380 U The variable overhead efficiency variance for July is: