A Level Economics AQA Practice Exam 2025 - Free Economics Practice Questions and Study Guide

The type of good that is both excludable and rivalrous in consumption is known as private goods. Private goods possess the characteristic of being excludable, meaning that individuals can be prevented from using them if they do not pay for them. Additionally, they are rivalrous, indicating that one person’s consumption of the good reduces its availability for others. A classic example of a private good is a sandwich; when one person eats it, it is no longer available for anyone else.

This definition highlights why private goods are the only category that fits both characteristics of excludability and rivalry perfectly. Public goods, on the other hand, are neither excludable nor rivalrous; quasi-public goods may be partially excludable but aren't entirely rivalrous; and common goods are rivalrous but not excludable, leading to overuse. Understanding these distinctions is crucial in economics as they help classify goods and analyze market behaviors associated with them.