Bixco Uses a Process Costing System and the Weighted Average

Bixco uses a process costing system and the weighted average method for its production of synthetic oils.During January materials totalling $300,000 were purchased, of which $150,000 was issued to production cost. Conversion costs of $100,000 were incurred. Production volume was 200,000 kg and of this 150,000 kg was sold. The cost of sales for January was:

A) $250,000
B) $225,000
C) $187,500
D) $162,500