Standard costs for one bag:
Standard Quantity Standard cost per bag
Direct Material 20 pounds $8.00
Direct Labor 0.1 hours $1.10
Variable Overhead 0.1 hours $0.40

The company had no beginning inventories of any kind on January 1. Variable overhead is applied to production on the basis of standard direct-labor hours. During January, the company recorded following activity:
Production: 4000 bags
Direct materials purchased: 85,000 pounds at a cost of $32,300
Direct-labor worked: 390 hours at a cost of $4875
Variable overhead incurred: $1475
Inventory of direct materials on January 31: 3000 pounds

Total Variance (both rate & efficiency) for variable overhead for January is?

My Calculations:
Rate: $1475-(390*4)=85F
Efficiency: (390*4)-(400*4)=40F
Total variance for variable overhead: 85F-40F= 45F

I don't think that is right but I am not quite sure what I am doing wrong. Any help would be greatly appreciated. Thank you