OPERATIONS MANAGEMENT IN THE SUPPLY CHAIN: DECISIONS & CASES (Mcgraw-hill Series Operations and Decision Sciences)
7th Edition
ISBN: 9780077835439
Author: Roger G Schroeder, M. Johnny Rungtusanatham, Susan Meyer Goldstein
Publisher: McGraw-Hill Education
expand_more
expand_more
format_list_bulleted
Concept explainers
Question
Chapter 9, Problem 2P
a)
Summary Introduction
To determine: The control limits for a p-chart.
b)
Summary Introduction
To determine: Whether the process is under control.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
A manufacturer uses statistical process control to control the quality of the firm's products. Samples of 50 of Product A are taken, and a defective/acceptable decision is made on each unit sampled. For Product B, the number of flaws per unit is counted. What type(s) of control charts should be used?
Select one:
a. c-chart for A, mean and range charts for B
b. p-chart for A , mean and range charts for B
c. c-chart for both A and B
d. p-chart for A, c-chart for B
e. p-charts for both A and B
Twenty samples of 100 items each were inspected when a process was considered to be operating satisfactorily. In the 20 samples, a total of 140 items were found to be
defective.
(a) What is an estimate of the proportion defective when the process is in control?
(b) What is the standard error of the proportion if samples of size 100 will be used for statistical process control? (Round your answer to four decimal places.)
(c) Compute the upper and lower control limits for the control chart. (Round your answers to four decimal places.)
UCL =
LCL =
Five data entry operators work at the data process-ing department of the Birmingham Bank. Each day for 30 days,
the number of defective records in a sample of 250 records typedby these operators has been noted, as follows:
a) Establish 3s upper and lower control limits.b) Why can the lower control limit not be a negative number?
c) The industry standards for the upper and lower control lim-its are 0.10 and 0.01, respectively. What does this imply about
Birmingham Bank’s own standards?
Chapter 9 Solutions
OPERATIONS MANAGEMENT IN THE SUPPLY CHAIN: DECISIONS & CASES (Mcgraw-hill Series Operations and Decision Sciences)
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, operations-management and related others by exploring similar questions and additional content below.Similar questions
- 6. The defect rate for your product has historically been about 4.50%. For a sample size of 500, the upper and lower 3-sigma control chart limits are: Part 2 UCLp = _______ (enter your response as a number between 0 and 1, rounded to four decimal places). The Standard deviation of defect rate of product is given __________. The Upper and Lower 3-sigma control charts limits are: UCLp ________ LCLp ________arrow_forwardUsing samples of 200 credit card statements, an auditor found the following: Sample 1 2 3 4 Number with errors 4 2 5 9 a. Determine the fraction defective in each sample. b. If the true fraction defective for this process is unknown, what is your estimate of it? c. What is your estimate of the mean and standard deviation of the sampling distribution of fractions defective for samples of this size? d. What control limits would give an alpha risk of .03 for this process? Page 457 e. What alpha risk would control limits of .047 and .003 provide? f. Using control limits of .047 and .003, is the process in control? g. Suppose that the long-term fraction defective of the process is known to be 2 percent. What are the values of the mean and standard deviation of the sampling distribution? h. Construct a control chart for the process, assuming a fraction defective of 2 percent, using two-sigma control limits. Is the process in control? Can you show me the steps and formulas using excelarrow_forwardDESIGNING A CONTROL CHART EXAMPLE Fujiyama Electronics, Inc. has been having difficulties with circuit boards purchased from an outside supplier. Unacceptable variability occurs between two drilled holes that are supposed to be 5 cm apart on the circuit boards. Thirty samples of 4 boards each were taken from shipments from the supplier as shown in the data listed below. Construct x and R charts for the process using the following data. DATA Sample No Samples 1 4.92 4.26 4.94 4.29 2 4.65 5.54 5.00 5.42 3 5.77 5.26 4.76 4.79 4 6.25 4.88 5.66 4.44 5 5.27 5.41 6.02 4.91 6 5.22 5.38 5.08 4.65 7 5.47 4.68 4.56 4.70 8 5.71 4.54 4.17 4.87 9 5.24 5.58 4.72 5.41 10 4.42 5.18 4.79 4.73 11 5.14 4.26 4.71 5.48 12 4.92 5.78 5.50 5.05 13 5.79 3.83 4.30 4.78 14 4.92 4.80 4.75 5.59 15 5.68…arrow_forward
- A metal fabricator produces connecting rods with an outer diameter that has a 1" ± 0.04 inch specification. A machine operator takes several sample measurements over time and determines the sample mean outer diameter to be 1 inch with a standard deviation of 0.008 inch. Calculate the process capability. 1.44 1.31 2.50 1.67 1.61arrow_forwardUsing samples of 197 credit card statements, an auditor found the following: Sample 1 3 errors Sample 2 3 errors Sample 3 5 errors Sample 4 9 errors 1. what alpha risk would control limits of .0470 and .0038 provide? 2. Using control limits of .0470 and .0038, is the process in control? 3. Construct a control chart for the process, assuming a fraction defective of 2 percent, using two-sigma control limits. Is the process in control?arrow_forward1. The data shown in Table 1 are x and R values for 20 samples of size n= 5 taken from a process producing bearings. The measurements are made on the inside diameter of the bearing, with only the last three decimals recorded (i.e., 31.6 should be 0.50316). Please show all your work for full credit. (a) Set up x and R charts on this process. Does the process seem to be in statistical control? If necessary, revise the trial control limits. (b) Assume that diameter is normally distributed. Estimate the process standard deviation. Sample R Sample R 1 31.6 4 11 29.8 4 33.0 3 12 34.0 4 35.0 4 13 33.0 10 4 32.2 4 14 34.8 4 5 33.8 38.4 31.6 15 35.6 7 3 16 30.8 7 4 17 33.0 5 8 36.8 10 18 31.6 3 9. 35.0 15 19 28.2 9 10 34.0 6 20 33.8 Table 1: Bearing Diameter Dataarrow_forward
- Over a period of 12 consecutive production hours, samples of size 50 resulted in the following proportions of defective items: (given) a. What are the three-sigma control limits for this process?b. Do any of the sample points fall outside of the control limits?c. The company claims a defect rate of 3 percent for these items. Are the observed proportions consistent with a target value of 3 percent defectives? What difficulty would arise if the control limits were based on a target value of 0.03? In view of the company’s claims, what difficulty would arise if the control limits computed in part (a) were used?arrow_forwardIf there are 400 total defects from 8 samples, each sample consisting of 20 individual items in a production process, what is the fraction defective that can be used in a "p" chart for quality control purposes?arrow_forwardManagement at Webster Chemical Company is concerned as to whether caulking tubes are being properly capped. If a significant proportion of the tubes are not being sealed, Webster is placing its customers in a messy situation. Tubes are packaged in large boxes of 135. Several boxes are inspected, and the following numbers of leaking tubes are found: View an example Sample 1 2 3 Get more help. 4 Tubes 7 7 8 5 1 5 6 7 Calculate p-chart three-sigma control limits to assess whether the capping process is in statistical control. The UCL, equals 1 Sample 8 8 9 10 11 12 13 14 Tubes 7 2 4 8 6 9 MacBook Pro 3 Sample 15 16 17 18 19 20 Total Tubes 8 3 3 5 and the LCL equals (Enter your responses rounded to three decimal places. If your answer for LCL, is negative, enter this value as 0.) 3 6 104 Clear all Check answer Oarrow_forward
- Please show all workarrow_forwardA metal fabricator produces connecting rods with an outer diameter that has a 1 ± 0.04 inch specification. A machine operator takes several sample measurements over time and determines the sample mean outer diameter to be 1.002 inches with a standard deviation of 0.009 inch. Calculate the process capability. 1.56 1.62 1.48 1.41 1.35arrow_forwardTwelve samples, each containing five parts, were takenfrom a process that produces steel rods at Emmanuel Kodzi’sfactory. The length of each rod in the samples was determined.The results were tabulated and sample means and ranges werecomputed. The results were: a) Determine the upper and lower control limits and the overallmeans for x -charts and R -charts.b) Draw the charts and plot the values of the sample means andranges.c) Do the data indicate a process that is in control?d) Why or why not?arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Practical Management ScienceOperations ManagementISBN:9781337406659Author:WINSTON, Wayne L.Publisher:Cengage,
Operations ManagementOperations ManagementISBN:9781259667473Author:William J StevensonPublisher:McGraw-Hill Education
Operations and Supply Chain Management (Mcgraw-hi...Operations ManagementISBN:9781259666100Author:F. Robert Jacobs, Richard B ChasePublisher:McGraw-Hill Education
Purchasing and Supply Chain ManagementOperations ManagementISBN:9781285869681Author:Robert M. Monczka, Robert B. Handfield, Larry C. Giunipero, James L. PattersonPublisher:Cengage Learning
Production and Operations Analysis, Seventh Editi...Operations ManagementISBN:9781478623069Author:Steven Nahmias, Tava Lennon OlsenPublisher:Waveland Press, Inc.
Practical Management Science
Operations Management
ISBN:9781337406659
Author:WINSTON, Wayne L.
Publisher:Cengage,
Operations Management
Operations Management
ISBN:9781259667473
Author:William J Stevenson
Publisher:McGraw-Hill Education
Operations and Supply Chain Management (Mcgraw-hi...
Operations Management
ISBN:9781259666100
Author:F. Robert Jacobs, Richard B Chase
Publisher:McGraw-Hill Education
Purchasing and Supply Chain Management
Operations Management
ISBN:9781285869681
Author:Robert M. Monczka, Robert B. Handfield, Larry C. Giunipero, James L. Patterson
Publisher:Cengage Learning
Production and Operations Analysis, Seventh Editi...
Operations Management
ISBN:9781478623069
Author:Steven Nahmias, Tava Lennon Olsen
Publisher:Waveland Press, Inc.