Alamo Rent-A-Car executives believe that Alamo accounts for about 50% of all Cadillacs that are rented. To test this belief, a researcher randomly identifies 20 major airports with on-site rental car lots. Observers are sent to each location and instructed to record the number of rental company Cadillacs observed in a four-hour period.
About 500 are observed, and 30% are observed being returned to Alamo. What are the implications of this finding for the Alamo executives' belief?