Assignment:
As part of the process for improving the quality of their cars, Toyota engineers have identified a potential improvement to the process that makes a washer that is used in the accelerator assembly. The tolerances on the thickness of the washer are fairly large since the fit can be loose, but if it does happen to get too large, it can cause the accelerator to bind and create a potential problem for the driver. (Note: This part of the case has been fabricated for teaching purposes and none of these data were obtained from Toyota.)
Let's assume that as a first step to improving the process, a sample of 40 washers coming from the machine that produces the washers was taken and the thickness measured in millimeters. The following table has the measurements from the sample:
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| 2.1 |
1.8 |
1.7 |
1.9 |
1.9 |
2.1 |
2.1 |
2.4 |
1.7 |
1.9 |
| 1.8 |
2.2 |
1.7 |
2.0 |
1.9 |
2.2 |
2.0 |
1.6 |
2.0 |
2.1 |
| 2.0 |
1.8 |
1.7 |
1.9 |
1.7 |
1.8 |
1.8 |
2.2 |
2.1 |
2.1 |
| 1.5 |
1.8 |
2.1 |
1.6 |
1.8 |
1.6 |
2.1 |
2.4 |
2.2 |
2.1 |
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If there are an upper and lower specification, where the upper thickness limit is 2.4 and the lower thickness limit is 1.5, what would be the Cpk for the process if it were centered between the specification limits (assume the process standard deviation is the same)? (Round your intermediate calculations and final answer to 4 decimal places.)