Calculate the process capability index for Exercise 21.34. Does the value of this index indicate that the production process is poor? Explain.

In exercise 21.34

The seats for the F-150 series Ford trucks are manufactured by Lear Seating. The frames must be 1, 496 mm wide with specification limits LSL = 1, 486 mm and USL = 1, 506 mm. Frames that are wider than 1, 506 mm or narrower than 1, 486 mm result in assembly problems because seat cushions and/or other parts won’t fit. The process is tested by drawing random samples of five frames every 2 hours. The last 25 samples were recorded. What can we conclude from these data?