Final answer:
A shift to the right in the supply curve is likely the reason for more computers being sold at lower prices; this is due to factors like technological advancements, increased competition, and improved distribution, which reduce costs and increase market supply.
Step-by-step explanation:
In the market for Macbooks, a shift in demand or supply that leads to more computers being sold at lower prices can be explained through the law of demand and law of supply. If we assume that the quality of the computers has not declined, a significant shift to the right in the supply curve would likely explain why more computers are selling at lower prices. This can occur for several reasons, such as technological advances reducing production costs, an increase in the number of sellers, or improvements in logistics and distribution channels.
On the other hand, a shift in demand, which happens when an economic factor causes a different quantity to be demanded at every price, could also explain the increase in quantity sold, but would more typically be associated with higher prices unless the supply has concurrently increased.
A sketch of the supply and demand diagram would show the supply curve shifting to the right, resulting in a new equilibrium point where a greater quantity is sold at a lower price. This scenario aligns with common economic observations where technological improvements and increased competition lead to lower prices and increased consumption.