The quantity demand of any good is the amount of the good that buyers are willing and able to purchase. As we will see, many things determine the quantity demanded of any good, but when analyzing how markets work, one determinant plays a central role the price of the good If the price of ice cream rose to $ 20 per scoop, you would buy less ice cream. You might buy frozen yogurt instead. If the price of ice cream fell to $0.20 per scoop, you would buy more. Because the quantity demanded falls as the price rises and rises as the price, falls, we say that the quantity demanded is negatively related to the price. This relationship between price and quantity demanded is true for must goods in the economy and in fact is so pervasive that economists call it the law of demand: Other things equal when the price of a good rises, the quantity demanded of the good falls, and when the price falls, the quantity demand rises. Shows how many ice-cream cones Catherine buy...