Final answer:
To ensure accurate sales recording, unit prices on the duplicate sales invoices are typically compared with an approved master price list. This is part of an internal control process to verify pricing consistency and prevent errors or fraud in the sales process.
Step-by-step explanation:
To determine that sales are accurately recorded, the unit prices on the duplicate sales invoices are normally compared with an approved master price list. This process helps ensure that the prices charged for goods or services are consistent with the company's authorized pricing structure and aren't subject to unauthorized alterations. It serves as an internal control mechanism to prevent errors or fraud in the sales process. Comparing invoice prices to a master price list is a crucial step in verifying the accuracy of recorded transactions before any further processing in the accounting system, such as recording in the sales journal or updating the accounts receivable master file.