Sales value of production W (12,000 units × $10) $120,000 X (10,000 units × $12) $120,000 Joint production costs will be apportioned equally between the two products as the sales value of production is the same for each product. Joint production costs allocated to X = $776,160/2 = $388,080 Value of closing inventory = 2,000/10,000 × $388,080 = $77,616