Let’s look at an example. A supermarket has a supply of 600 pounds of tomatoes at $1.99 a pound. After two days, customers have bought only 100 pounds. Soon 600 more pounds are coming to the store manager has a problem-a surplus of tomatoes. In other words, she has an oversupply–too many-so she lowers the price to $1.09 a pound. At this low price, customers soon buy all 500 pounds. This is the equilibrium price.