Problem 4 (15 Marks) Quality control engineers at Advanced Electronics (AE) are monitoring the quality level of AE's main production line. The engineers took 20 samples with each sample containing 40 units of the same products. After careful inspection, they found some of the products are defective. The results of inspection with a total of 28 defective units are shown in the following table. The engineers decided to use p chart to further analyze the quality of the production. Table: Quality Level Data Sample # Defective Units (D) Defective Rate Sample # Defective Units (D) Defective Rate (D/40) (D/40) 1 0.025 11 2 0.050 1 0.025 12 0.025 0.025 13 0.050 3 0.075 1 0.025 5 2 0.050 15 1 0.025 0.025 16 1 0.025 7 0.050 17 1 0.025 8 0.025 18 2 0.050 0.025 19 0.025 10 0.025 20 0.050 Total 28 1 2 3 4 1 2 1 14 6 1 2 1 9 1 2 1 Formulas to determine the center line and control limits of a p chart are p = , D and p +3 x px(1-P) respectively TEX 71 1) Based on the given data, calculate the center line, upper and lower control limits of the p chart 2) Based on the results calculated in 1) and data in the above table, draw the corresponding p chart in your answer paper. The chart may not be precise but should reflect in general the production quality, 3) Briefly explain if the quality of the production is in control" or "out of control" 4) IF AE management decides that the defective rate of the production should not exceed 2%, (In answering 4.1) and 4.2) below, you do NOT need to draw a new p chart) 4.1) indicate if the production process is "in control" or "out of control". 4.2) briefly explain why it is in control" or "out of control" as you indicated in 4.1) above