Question

Question 4 Company JW produces large towels. They are supposed to be brightly colored and have a fringe on each end. A towel is selected from finished towels at regular intervals and subjected to intense inspection in search of any defects. A defect can be a hole, a missing fringe, a stain, a badly dyed spot, etc. Each occurrence counts as a distinct defect. Data on 12 sample towels are given in Table QB4 Towel2 3 4 5 6 79 10 11 12 4 Number of Defects 230 3 2 3 Table QB4 (a) What type of control chart should be used here? Why? (b) What is the centerline of the chart? c) What is the Lower control limit and the Upper control limit? d) What statistic should be plotted on the control chart for each sample? ) Draw the control chart on a piece of graph paper (2 marks) (2 marks) (4 marks) (2 marks) (5 marks) (3 marks) (2 marks Is this system under control? Explain What action should the quality control engineer take? - End of Paper -

Answer 1

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