To complete the Inventory account, we need to post the relevant totals from the subsidiary journals. Inventory is an asset account, so it increases with debits and decreases with credits.

To complete the Inventory account, we need to post the relevant totals from the subsidiary journals. Inventory is an asset account, so it increases with debits and decreases with credits.

First, we need to calculate the missing "Cost of sales" figures for the Sales journal and Sales returns journal. The problem states that "All goods are sold at a constant mark-up of 25% on cost."

• Selling Price = Cost + (Mark-up % $\times$ Cost)
• Selling Price = Cost $\times$ (1 + Mark-up %)
• Cost = Selling Price / (1 + Mark-up %)

Step 1: Calculate Cost of Sales from Sales Journal.
Sales (Selling Price) = R 8 200
Mark-