Question

A grinding process has an upper specification of 1.649 inches and a lower specification of 1.507 inches. A sample of parts had a mean of 1.57 inches with a standard deviaiton of 0.026 inches.

Round your answer to four decimal places.
What is the process capability index for this system?

Answer 1

The process capability index for this system is 0.9103

Explanation:

Upper specification = 1.649 inches

Lowe Specification = 1.507 inches

Mean = 1.57 inches

Standard Deviation = 0.026 inches

Process Capability Index = PCI

PCI = (Upper specification - lower specification)/6(standard deviation)

So, we get,

PCI = (1.649 - 1.507)/((6)(0.026))

PCI = 0.142/0.156

PCI = 0.9102564

To four decimal places, we get,

PCI = 0.9103