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 c
ar loader is set to put 69 tons of coal into each car. The actual weights of coal loaded into each car are normally distributed, with mean μ = 69 tons and standard deviation σ = 0.9 ton. What is the probability that one car chosen at random will have less than 68.5 tons of coal?
