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During a discussion, one auditor noted that her approach to testing sales transactions was to select a random sample of recorded sales and trace back through the system to supporting documents, noting that all items billed were shipped and were invoiced at correctprices. She stated that she then had high confidence about the correctness of the sales account, and, therefore, having performed a dual-purpose test, the remaining work on sales (assuming the procedures also evidenced the working of control procedures) could be limited.

A second auditor disagreed. Her approach was to select evidence of shipments, such as prenumbered shipping documents, and then trace forward through the system to the actual invoice, noting the existence of control procedures and the correctness of the invoice processing. If no exceptions were noted, however, she agreed with the first auditor that the remaining audit work on the sales account could be limited.

1. Which auditor is right; or are both right? Explain.
2. What assertion is the second auditor testing?
3. What is a dual-purpose test? Explain whether the tests performed by both of the auditors are dual-purpose tests.