Most railroad cars are owned by individual railroad companies. When a car leaves its home railroad’s trackage, it becomes part of the national pool of cars and can be used by other railroads. A particular railroad found that each month 15% of its boxcars on its home trackage left to join the national pool and 40% of its cars in the national pool were returned to its home trackage. A company begins on January 1 with all its cars on its home trackage. What fraction will be there on March 1? At the end of the year? In the long run what fraction of a company’s cars will be on its home trackage.