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: $47,155
	Total variable manufacturing overhead variance: $5,520 favorable
	Standard machine setups allowed for actual production: 3,010 setups
	Actual machine setups incurred: 2,940 setups

The standard variable overhead rate per machine setup is:

$16.04

$17.92

$13.81

$17.50