Causwell Company began 2021 with 18,000 units of inventory on hand. The cost of each unit was $5.00. During 2021 an additional 38,000 units were purchased at a single unit cost, and 28,000 units remained on hand at the end of 2021 (28,000 units therefore were sold during 2021). Causwell uses a periodic inventory system. Cost of goods sold for 2021, applying the average cost method, is $166,600. The company is interested in determining what cost of goods sold would have been if the FIFO or LIFO methods were used.

Required:
a. Determine the cost of goods sold for 2018 using the FIFO method. [Hint: Determine the cost per unit of 2018 purchases.]
b. Determine the cost of goods sold for 2018 using the LIFO method. (Do not round intermediate calculations.)