Suppose the demand for a movie ticket can be written as:
P = 10 – QS for senior citizens and P = 18 – Q G for all other consumers.
If the cinema can offer tickets to a movie at zero marginal cost and can verify the purchaser’s age, what prices will be charged?
Seniors get in for free; everyone else pays £18.
Seniors pay £10; everyone else pays £18.
Seniors pay £5; everyone else pays £9.
Everyone pays £7.