Products X, Y, and Z are produced from the same process at a cost of $5,200. Five thousand pounds of raw material yields 1,500 X, 2,500 Y, and 1,000 Z. Selling prices are: X $2 per unit, Y $4 per unit, Z valueless. The ending inventory of X is 50 units. What is the value of the ending inventory if joint costs are allocated using net realizable value?

• $21.67.
• $31.20.
• $40.00.
• $42.00.