Case Study 2: Quality Management Your line manager has become increasingly concerned about the product and service quality. This results from a surge in the number of customers who have contacted her to highlight problems they have encountered while shopping at the Pet Kingdom store. The complains seem to focus on two areas; billing errors being made at the checkout and variations in the weight of Pet Kingdom branded dried dog food bags. To better understand the situation, Ms Lionheart has requested detailed data to be collected. Table 3 shows the data from the audit of 50 random bills per day issued over the past 30 days. Table 4 presents the weight sampling data (mean and range in kg) for 27 random samples of five observations each taken from the daily dog food deliveries. Ms Lionheart noticed that the number of billing errors increased in the last third of the month. She knows that the company wants high quality standards and wonders if both processes meet 3 sigma standards. She wants you to analyse the available data and produce a short report (1,000 words ± 10%) with all relevant tables and figures, to address the highlighted issues. In your report you need to consider the following for both sets of data: 1. Analyse and explain the data. 2. Set up appropriate 3-sigma control limits and generate the control charts. Explain your approach. What does 3-sigma indicate about the acceptable quality? 3. Is the process in control? Explain. 4. Explain your findings and the consequences. 5. How could implementing TQM help the company? 6. Provide two key recommendations for the company. Table Day 1 2 3 4 5 6 7 8 9 10 2 3 4 Number of incorrect bills issued at checkout (50 observations) Number of Incorrect Bills 5 6 7 8 9 10 11 12 13 14 2 2 1 2 2 3 2 2 1 2 Mean 44.96 44.98 44.96 44.97 45.02 45.03 45.04 Day 11 12 13 14 45.02 45.08 45.12 45.07 45.02 45.01 44.98 15 16 17 18 19 20 Number of Incorrect Bills 1 2 0.41 0.37 0.39 0.40 0.39 0.42 0.38 0.40 0.41 0.38 0.41 0.40 3 3 2 3 2 2 1 3 Table: Dog food weight (kg) samples (5 observations) Sample 1 Day 21 22 23 24 16722 25 26 27 25 28 29 30 Range Sample Mean 0.42 15 45.00 0.39 16 44.95 17 18 19 20 21 22 23 24 Number of Incorrect Bills 44.94 44.94 44.73 44.95 44.93 44.96 44.99 45.00 45.03 45.04 45.03 3 3 3 4 5 5 6 8 5 5 Range 0.39 0.41 0.43 0.40 0.38 0.41 0.39 0.41 0.40 0.44 0.42 0.38 0.40