Answer to Question #7904 in Statistics and Probability for James

Question

During production in a cement plant, test cubes of cement are taken at regular intervals and their compressive strengths, in kg m-2, determined. Analysis of data over a long time has shown that the compressive strength of these samples is normally distributed with a mean 0.0468 kg m-2 and a standard deviation 1.6 × 10-3 kgm-2.
Calculate the probability that a randomly chosen sample has a compressive strength below 0.045 kg m-2.