Question

University Hospital has been concerned with the number of errors found in its billing statements to...

University Hospital has been concerned with the number of errors found in its billing statements to patients. An audit of 100 bills per week over the past 12 weeks revealed the following number of errors:

Develop control charts with z = 3: (a) CL, (b) UCL, (c) LCL. (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:

LCL:

Is the process in control?

Week Number of Errors
1 4
2 5
3 6
4 6
5 3
6 2
7 6
8 7
9 3
10 4
11 3
12 4

Homework Answers

Answer #1

To solve this given problem, we'll first find the mean and standard deviation of the five samples through MS Excel functions Average and STDEV respectively

The mean of the given data = 4.42

The Standard deviation of the given data = 1.56

Sample size = n = 10

Since the required sigma level = 3

UCL = Mean + [3 x (SD / Sqrt(n)] = 4.42 + [3 x (1.56/10)] = 4.89

LCL = Mean - [3 x (SD / Sqrt(n)] = 4.42 - [3 x (1.56/10)] = 3.95

So the control limits are (3.95, 4.89)

Since, many values fall outside the control range of (3.95, 4.89), the process is out of control.

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
A production manager at a Contour Manufacturing plant has inspected the number of defective plastic molds...
A production manager at a Contour Manufacturing plant has inspected the number of defective plastic molds in five random samples of 35 observations each. Following are the number of defective molds found in each sample: 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: LCL: Sample Number of Defects Number of Observations in Sample...
4a.) The management of a hotel is worried about the number of customer complaints. A detail...
4a.) The management of a hotel is worried about the number of customer complaints. A detail analysis shows the number of complaints in 100 feedback per week over the past 12 weeks. a) Develop control charts with z = 3. b) Is the process in control? Week Number of complaints 1 4 2 5 3 6 4 6 5 3 6 2 7 6 8 7 9 3 10 4 11 3 12 4
A restaurant is improving its processes, and is currently focusing on the final bill presented to...
A restaurant is improving its processes, and is currently focusing on the final bill presented to customers. The manager samples 50 bills per day for 12 days, and checks to see how many are incorrect using a z-value of 3. [ Select ] Is the billing process consistent (in other words, is it in control), or do special cause events appear to be present? [ Select ] What is the UCL? [ Select ] What is the LCL? Day Day...
A university is concerned about the presence of grade​ inflation, which is defined as an increase...
A university is concerned about the presence of grade​ inflation, which is defined as an increase in the average GPA of the​ institution's students over time without a comparable increase in academic standards. To investigate this​ phenomenon, the average GPA for the student body was recorded over the past 11​years, as shown in the table to the right. Construct a 90% confidence interval for the slope. LCL=    UCL= ​(Round to three decimal places as​ needed.) ​Year GPA 1           3.07 2           ...
A university is concerned about the presence of grade inflation, which is defined as an increase...
A university is concerned about the presence of grade inflation, which is defined as an increase in the average GPA of the institution's students over time without a comparable increase in academic standards. To investigate this phenomenon, the average GPA for the student body was recorded over the past 11 years, as shown in the table to the right. Construct a 90% confidence interval for the regression slope. Year GPA Year GPA 1 3.08 7 3.08 2 2.88 8 2.98...
Based on your recommendations, Mr. Miller improved shop operations and successfully reduced the number of customer...
Based on your recommendations, Mr. Miller improved shop operations and successfully reduced the number of customer complaints. To maintain good service, Mr. Miller asked you to keep monitoring the wait times of oil change customers at the shop. First, you decide to create an x-bar chart to monitor the central tendency (i.e., mean). But you know that we sometimes overlook a problem if we use only an x-bar chart. Therefore, you decide to create an R-chart to monitor the process...
Using samples of 200 credit card statements, an Auditor found the following: ---Sample Number: 1    2    ...
Using samples of 200 credit card statements, an Auditor found the following: ---Sample Number: 1    2     3     4     5     6     7   8 9    10    11   12   13   14   15 Number of Errors:    17  12   11   12   10    10   17   15   12   13    15    10     7     8      10 Determine lower and upper control limits for the fraction of errors using three-sigma limits. Question 8 options: 0 , .126 .017 , .101 .026 , .093 .009 , .109 None of the Above The Quality Control...
As a hospital administrator of a large​ hospital, you are concerned with the absenteeism among​ nurses'...
As a hospital administrator of a large​ hospital, you are concerned with the absenteeism among​ nurses' aides. The issue has been raised by registered​ nurses, who feel they often have to perform work normally done by their aides. To get the​ facts, absenteeism data were gathered for the last three​ weeks, which is considered a representative period for future conditions. After taking random samples of 60 personnel files each​ day, the following data were​ produced:                                                                                                                                         Day Aides Absent Day...
The data shows the number of weeks employed and the number of errors made per day...
The data shows the number of weeks employed and the number of errors made per day for a sample of assembly line workers. Weeks (x) Errors (y) 1 20 1 18 2 16 4 10 4 8 5 4 6 3 8 1 10 2 11 1 12 0 12 1 Develop a scatter plot.  Describe the relationship between weeks and errors. Use a simple least square regression equation to predict the number of errors. Is there a significant relationship between...
You are the newly appointed assistant administrator at a local hospital, and your first project is...
You are the newly appointed assistant administrator at a local hospital, and your first project is to investigate the quality of the patient meals put out by the food-service department. You conducted a 10-day survey by submitting a simple questionnaire to the 400 patients with each meal, asking that they simply check off that the meal was either satisfactory or unsatisfactory. For simplicity in this problem, assume that the response was 1,000 returned questionnaires from the 1,200 meals each day....