Final answer:
A third-party guarantee involves a commitment from a friend or family member to pay for someone's expenses, while a third-party payer is an insurance company or government entity that covers the costs.
Step-by-step explanation:
A third-party guarantee involves a commitment from a friend or family member to pay for someone's expenses, while a third-party payer is an insurance company or government entity that covers the costs. For example, if a friend guarantees to pay for someone's hospital bills, that is a third-party guarantee. On the other hand, if an insurance company covers the costs of medical treatment, that is a third-party payer.