Goods that are purchased together because they are consumed together are known as what?

• A. Substitute Goods
• B. Complementary Goods
• C. Independent Goods
• D. Joint Demand

Answer: (B)

Two goods that are bought together because people use them together are complementary goods. This relationship means the demand for one tends to be linked to the demand for the other, so a fall in the price of one can boost the demand for its partner. For example, printers and ink cartridges: when printers are cheaper or more popular, more ink cartridges are purchased as well. This is driven by how closely the items are used together, creating a negative cross-price elasticity of demand.

Substitute goods would replace each other (a fall in the price of one increases demand for the other), independent goods have no link in demand, and joint demand is a broader term that can describe two goods demanded together but doesn’t specify the strong paired-use relationship that defines complementary goods.