A production manager at a Contour Manufacturing plant has inspected the number o

Question

A production manager at a Contour Manufacturing plant has inspected the number of defective plastic molds in five random samples of 25 observations each. Following are the number of defective molds found in each sample: Number of Number of Observations Sample Defects in Sample 25 25 25 25 25 125 2 3 4 Total Construct a 3-sigma control chart (z = 3) with this information. (If the lower control limit is negative, round the LCL to zero and all other answers to 2 decimal places, e.g. 15.25.) CL UCL Click if you would like to Show Work for this question: Open Show Work

Explanation / Answer

CL = Avg Fraction Defective
p(bar) = Total Number of Defects / Total Number of Observations
= 7/125 = 0.056

n = 25

Standard deviation of p = SQRT(p(1-p)/n) = sqrt((.056)(.944)/25) = 0.04598

UCL = Avg of p + 3 Std Error = p(bar) + 3 ?p =0.056 +3(.04598) = 0.19394

LCL = Avg of p - 3 Std Error = p(bar) - 3 ?p =0.056 - 3(.04598) = -0.08194

lower limit rounded to zero is =0.00

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.