Home › Forums › General Forums › Tools & Templates › Need Help with Control Chart Problem
This topic contains 6 replies, has 3 voices, and was last updated by MBBinWI 3 years, 5 months ago.
The sample size is n = 7. Xbar and R are computed for each sample. After 35 samples, it is found that
I found Xbar to be 7805 and R to be 1200.
(a) Set up and R charts for this process. Is this process in statistical control?
(b) Assuming that both charts exhibit control, estimate the process mean and standard deviation.
(c) If the quality characteristic is normally distributed and if specifications are 220 ±35, can the process meet the specifications? Estimate the fraction nonconforming.
(d) Assuming the variance to remain constant, state where the process mean should be located to minimize the fraction nonconforming. What would be the value of the fraction nonconforming under these conditions?
How would I find these information? I know I need to find LCL and UCL, but I don’t know how to.
DO YOUR OWN #$%^&*&@ HOMEWORK AND START PAYING ATTENTION IN CLASS. WE DON’T DO HOMEWORK ASSIGNMENTS ON THIS FORUM.
@Darth That sounds familiar. This guy ever meets you he will throw a chair at you.
Cripes, folks. A little diplomacy goes a long way.
Shawn — They’re right, this isn’t a site for getting homework assignments answered. We all had to suffer though it so those behind us must, too. Plus, that’s how you learn. As for the UCL and LCL, any statistical software program, including Excel, will help you get there. The rest you have to work through.
Marcy, you are obviously a Newbie. After dealing with folks like Shawn, if you don’t nip it in the bud the site gets swamped with people wanting you to do their homework, pick their projects and our all time favorite, select a topic for their Dissertations.
While people shouldn’t come to this forum to find someone to do their homework, at least we should be willing to point them in the right direction. For instance, a simple reminder that the control limits are 3 standard deviations above and below the mean? Real teachers don’t provide the answers or disparage those who ask for answers. They help them to find the answers for themselves.
@Straydog – but real “students” attempt an answer and provide their reasoning and ask what, if anything, they got wrong. They don’t just throw-up the question and say “answer this for me.”
© Copyright iSixSigma 2000-2017. User Agreement. Any reproduction or other use of content without the express written consent of iSixSigma is prohibited. More »