Final answer:
When the number of people attending a cinema increases, the amount of tickets sold also increases. Factors like the opening of new entertainment venues such as nightclubs or changes in local taxes can affect the demand and supply of movie tickets, influencing the number of tickets sold. Therefore, the correct answer is a. increases.
Step-by-step explanation:
If the number of people watching a movie in the cinema increases, this would lead to an increase in the amount of tickets sold. The relationship between the number of moviegoers and the amount of tickets sold is directly proportional, meaning that as one increases, so does the other.
This concept is a fundamental principle in supply and demand, a key aspect of economics. For instance, if three new nightclubs open, and they attract people away from the cinema because there's no cover charge, the demand for movie tickets would decrease, as reflected by a reduction in the number of tickets by six units at every price point.
Conversely, if a city eliminates a tax on local entertainment, this could result in a lower cost for moviegoers and the quantity supplied of movies at any given price might increase by 10%, potentially leading to more ticket sales, depending on how responsive consumers are to the price change. Therefore, the correct answer is a. increases.