The Richie Company uses a standard costing system in which variable manufacturing overhead is assigned to production on the basis of the number of machine setups. Data for the month of October include the following:
	Variable manufacturing overhead cost incurred: $36,814
	Total variable manufacturing overhead variance: $5,290 favorable
	Standard machine setups allowed for actual production: 2,770 setups
	Actual machine setups incurred: 2,700 setups

The standard variable overhead rate per machine setup is:

a. $15.20

b. $15.59

c. $13.63

d. $11.43