ASSIGNMENTS

Statistical Quality Control for Service Professionals

Assignment #$4$

$(10$ pts$)1.$

For a long time, you have noticed that your panels have many dirt and grease spots when they are packed and shipped out of your department. The customer says that something must be done to improve the situation. Can this problem be solved by the people on the production floor, or must a management team take the necessary action to bring about improvement?

Someone took the time to inspect $48$ parts at the final packing operation each day for twenty days. Using data, try to determine whether the problem is due to assignable causes or due to the way the process is set up$.$

$($Hint: Construct a p chart.$)$

$(5$ pts $)2.$ If $p=0\mathrm{.}05$ and the sample size of each subgroup is $150,$ then calculate the control limits for:

a$)p$ chart

b$)$ np chart

$(5$ pts$)3.$ Calculate the control limits for a c chart if $c=10.$

$\backslash$table$[[$days$,$defects,sampled$],[1,30,48],[2,27,48],[3,34,48],[4,23,48],[5,20,48],[6,33,48],[7,22,48],[8,24,48],[9,18,48],[10,34,48],[11,25,48],[12,20,48],[13,24,48],[14,23,48],[15,16,48],[16,19,48],[17,32,48],[18,26,48],[19,25,48],[20,25,48]]$