Final answer:
Validating a vendor invoice in an AP/CD process involves checking mathematical accuracy, comparing with purchase order and receiving report. It does not involve approval by purchasing manager.
Step-by-step explanation:
In an AP/CD process, validating a vendor invoice typically involves several steps to ensure accuracy and legitimacy. These steps include checking the invoice for mathematical accuracy, comparing the invoice with a copy of the purchase order, and comparing the invoice with a copy of the receiving report. However, having a copy of the invoice approved by the purchasing manager is not typically part of the validation process.