In a ready-mix plant, cylindrical samples are prepared and tested periodically to detect any mix problem and to ensure that the compressive strength is higher than the lower specification limit. The minimum target value was set at 5,000 psi. The compressive strength data shown in Table were collected. a. Calculate the mean, standard deviation, and the coefficient of variation of the data. b. Using a spreadsheet program, create a control chart for these data showing the lower specification limit. Is the plant production meeting the specification requirement? If not, comment on possible reasons. Comment on the data scatter.
Extracted text: Compressive Strength (psi) Compressive Strength (psi) Sample No. Sample No. 5595 11 6695 5139 12 5449 6359 13 5278 4 5192 14 6697 5 5188 15 5195 5241 16 6021 5964 17 5320 5875 18 5657 6155 19 6595 10 5115 20 5235 2. 3.