Coal is carried from a mine in West Virginia to a power plant in New York in hopper cars on a long train. The automatic hopper car loader is set to put 83 tons of coal into each car. The actal weights of coal loaded into each car are normally distributed, with mean =83 and standard deviation =1.4

a) what is the probability that 27 cars chosen at random will have a mean load weight x of less than 82.5 tons of coal?