See attached files.
Ricardo's Widgets makes a critical part for a popular brand of cell phones. Consider the data for 15 samples of size 4 of a key dimension for the part, show in the worksheet. Specifications are 0.110 +/- 0.015.
a. Compute control limits for an x-chart using the statistic R/d2 as an estimate of the standard deviation and using the actual standard deviation for the data. Why are they different?
b. Construct the x- and R-charts and an x-chart for the 'individuals' using the data. Interpret the results.
c. Estimate the process capability by using the actual sample standard deviation.© BrainMass Inc. brainmass.com July 20, 2018, 5:48 pm ad1c9bdddf
The solution is an annotated Word doc and Excel spreadsheet.