Consider a quality characteristic, X, with specification 11 ± 1.5 mm and this dimension in the finished goods is found to be normally distributed with standard deviation μ=0.3. 

 1. What is the quality level of a process? 

 2. If process mean, μ = 11.45, is the process centered?

3. If process mean, μ = 11.45 (±1.5σ shift), what is the percent defectives? 

 4. If process is centered, what will be the percent defectives?

 5. What is the quality level now? 

 6. If process mean, μ = 11.375, is the process centered? 

 7. If process mean, μ= 11.375 (±1.5σ shift), what is the percent defectives? 

 8. If process is centered, what will be the percent defectives?