A manufacturer of dustless chalk instituted a quality control program to monitor chalk density. The sample standard deviations of densities for 24 different subgroups, each consisting of n = 8 chalk specimens, were as follows: (0.203, 0.316, 0.096, 0.183, 0.233, 0.213, 0.320,
0.285, 0.144, 0.208, 0.053, 0.144, 0.275, 0.351,
0.159, 0.216, 0.389, 0.185, 0.153, 0.227, 0.275,
0.118, 0.089, 0.055)

Required:
Calculate limits for an S chart, construct the chart, and check for out-of-control points. If there is an out-of-control point, delete it and repeat the process