Question 3) A process that is considered to be under control measures an ingredient in ounces. Below are the last 10 samples (each of size n =5) taken. The population standard deviation is 1.36. 1 10 9 10 9 12 2 9 9 11 11 10 3 13 9 10 10 9 4 10 10 11 10 10 SAMPLES 5 12 10 9 11 10 6 10 10 8 12 9 a) What is the process standard deviation? What is ox? Answer: Sigma = 1.36 Sigma X-bar = 0.608 b) If z=3, what are the control limits for the mean chart? 7 10 11 10 8 9 8 13 10 8 10 8 9 8 8 12 12 9 10 10 12 9 8 12

A process that is considered to be under control measures an ingredient in ounces. Below are the last 10 samples (each of size n=5 ) taken. The population standard deviation is 1.36. a) What is the process standard deviation? What is X ? Answer: Sigma =1.36 Sigma X-bar =0.608 b) If z=3, what are the control limits for the mean chart