An automatic machine produces 5.0-millimeter bolts at a high rate of speed. A quality control program has been initiated to control the number of defectives. The quality control inspector selects 50 bolts at random and determines how many are defective. The numbers of defectives in the first 10 samples are 3, 5, 0, 4, 1, 2, 6, 5, 7, and 7.
a. Design a p-chart. Insert the mean proportion defective, UCL, and LCL.
b. Plot the proportion defective for the first 10 samples on the chart.
c. Interpret the chart.