Longberry Corporation manufactures and sells party items. The following representative direct labor hours and production costs are provided for a four-month period: Month Direct Labor Hours Production Costs May 3,600 $15,000 June 4.800 17,500 July 6,000 August 4.800 19.200 20,000 17.500 $70,000 Total Leta - = Fixed production costs per month Variable production costs per direct labor hour b - Number of months - Direct labor hours per month X Y = Total monthly production costs S = Summation The monthly production cost can be expressed as IX-aY- b X-a- bY Y-a + Y-6