In 1990, the town of Ham Harbor had a more-or-less free market in taxi services. Any respectable firm could provide taxi service as long as the drivers and cabs satisfied certain safety standards. Let us suppose that the constant marginal cost per trip of a taxi ride is $5, and that the average taxi has a capacity of 20 trips per day.

Let the demand function for taxi rides be given by D(p) = 1, 00020p, where demand is measured in rides per day, and price is measured in dollars. Assume that the industry is perfectly competitive.

I have a hard time finding the equilibrium price, a number I need in order to find the equilibrium number of rides per day.