Pam graduates from law school and gets a position in a law firm at four times her current income. At the same time the price of hamburger falls by 25 percent while other food prices stay the same. She notices that she buys less hamburger than she did before. Is she violating the law of demand?

No

Explanation:

Pam is not violating the law of demand. The law of demand suggests that the supply of a product varies with demand. When demand increases, price increases, when demand decreases, price decreases. Notice that Pam has decreased hamburger consumption, meaning it has contributed to the decrease in demand. If the demand for hamburgers has decreased, it is only natural that the price of hamburgers will decrease. It should be noted that even if the hamburger price had risen and Pam no longer consumed hamburgers, the law of demand would still not be violated. This is because the law of demand takes into account aggregate demand (from all consumers) rather than individual demand. So Pam could have stopped eating hamburger as a matter of preference for another item.