Alpha electronic company manufactures cathode ray tubes on mass production basis. At some intermediate point of production line, 10 samples of size 25 each have been taken. Tubes within each sample were classified into good or bad. The related data are given in the following table.

Construct a suitable control chart with 3 sigma limit and comment on the process.

Sample No. 1 2 3 4 5 6 7 8 9 10 No. of Defective Tubes 4 10 2 3 6 5 2 4 3 2 AppendixLO1