The price consumption curve shows how the optimal bundle changes with the change in prices of one good. For example, the student changed their purchase of books and snacks with a change in the prices of books. This relation between price changes of books and the quantity of books purchased helps derive the demand curve for books.
For each optimal bundle, the quantity of books purchased and the corresponding price of books are noted. This gives the quantity of books demanded by the student at each price. Now, quantity of books can be plotted against their corresponding prices on a graph. The resulting curve is the consumer's demand curve for books. It shows the relationship between the price of books and the quantity demanded by the student, all other factors being equal.
It is an individual demand curve that shows the relationship between the price of a particular product and the quantity demanded of that product by an individual consumer.
