1. In order to ensure the purity of their food products, RR Corporation measures the amount of contaminants present in parts per million. At their facility, on a particular production line, they might produce biscuits on one day and crackers the next.

The following data is from two different days of production. They want to use a short run chart to monitor their production process. Create the control limits and centerlines for a Nominal X-bar and R chart for the following data. Work this problem to 1 decimal place.

Nominal 20                                             Nominal 70

22                                                              80

15                                                              70

25                                                             65

23                                                              68

15                                                             72

20                                                              69

22                                                              70

25                                                              71

2. One of steel cable's key characteristics is tensile strength in PSI. The data listed below gives tensile strength for steel cable used in constructing bridges. Because the cable is manufactured in a continuous process, the best type of chart to use to monitor the production process is a moving average, moving range chart.

As the cable is made, a sample is taken every half-hour. Use n = 3 and the following information to create a moving average and a moving range chart. Work to whole numbers. 

What are the upper and lower control limits for Xbar, R, & S?

42,000
47,000
46,000
48,000
45,000
47,000
45,000
41,000
48,000
51,000
49,000
46,000