Specification limits for a particular characteristic of a product indicate the values at which the product will operate properly. Specification limits are set by engineering and are not determined by the data. The data must be examined to determine whether the product is within specifications. If the product is within specification limits, the process generating the product is often referred to as capable. For example, assume we have a product with an upper specification limit of

USL = 5.15

and a lower specification limit of

LSL = 4.0.

As long as our product falls within these limits our buyers will be happy. We now investigate the process used to manufacture the product and find that the process mean is 5 and the process standard deviation is 0.2.

a) Assuming the process is normally distributed, what percentage of items will fall outside the specification limits? (Round your answer to two decimal places.) b) Should we make changes in the process? If so, what would you suggest?

a. Yes, we should consider changes to the production process that would reduce this percentage

b. No, we should not consider changes to the production process.

c. Yes, we should consider changes to the production process that would increase this percentage.