Question 1

In 25 samples of 100 units each,75 units were found to be defective.Find the appropriate UCL and LCL for the p chart.

Accepted Answer

A) 0 to .0642 
B) 0 to .0828 
C) 0 to .0812 
D) .0129 to .0471 
E) 0 to .1324 
A) 0 to .0642 
B) 0 to .0828 
C) 0 to .0812 
D) .0129 to .0471 
E) 0 to .1324

Question 2

A fastener company produces a certain type of bolt for the automobile industry with a nominal (target)length of 2.00 inches.The specifications for the length of the bolt are 2.00 ± .006 inches.An automobile manufacturer will only purchase from this company if the sigma level of capability of the process is at least 4.If the process mean is equal to 2.001,determine the maximum process standard deviation necessary for the fastener manufacturing company in order to qualify as a supplier for the automobile manufacturing company.

Accepted Answer

A) .0125 
B) .005 
C) .00125 
D) .00025 
A) .0125 
B) .005 
C) .00125 
D) .00025

Question 3

Sources of process variations that are inherent to the process design are called ___________ causes of variation.

Accepted Answer

A) common 
B) assignable 
C) unusual 
D) expected 
A) common 
B) assignable 
C) unusual 
D) expected

Question 4

Common causes of process variation:

Accepted Answer

A) Are sources of unusual process variation. 
B) Usually must be remedied by management. 
C) Usually must be remedied by local supervision. 
D) Always exist together with assignable causes of variation. 
E) Can never be remedied or reduced. 
A) Are sources of unusual process variation. 
B) Usually must be remedied by management. 
C) Usually must be remedied by local supervision. 
D) Always exist together with assignable causes of variation. 
E) Can never be remedied or reduced.

Question 5

A motorcycle manufacturer produces the parts for its vehicles in different locations and transports them to its plant for assembly.In order to keep the assembly operations running efficiently,it is vital that all parts be within specification limits.One important part used in the assembly is the engine camshaft,and one important quality characteristic is the case hardness depth.Specifications state that the hardness depth must be between 3.0 mm and 6.0 mm.To investigate the process,the quality control engineer selected 25 daily subgroups of n = 5 and measured the hardness depth.The process yielded a mean of the means $\overline { \overline { x } }$

= 4)50 and an average range = 1.01.Calculate the control limits for the X-bar chart.

Accepted Answer

A) [4.345,4.655] 
B) [3.49,5.51] 
C) [3.917,5.083] 
D) [2.365,6.635] 
A) [4.345,4.655] 
B) [3.49,5.51] 
C) [3.917,5.083] 
D) [2.365,6.635]

Question 6

A manufacturer of windows produces one type that has a plastic coating.The specification limits for the plastic coating are 30 and 70.From time to time the plastic coating can become uneven.Therefore,to keep the coating as even as possible,thickness measurements are periodically taken at four different locations on the window.15 subgroups were observed,each consisting of four thickness measurements,with the following results: mean of the means = $\overline { \overline{ x } }$

= 50.05,and average range of 8.85.Find the sigma level capability of the process.

Accepted Answer

A) 4.64 
B) -4.66 
C) 7.83 
D) 2.25 
A) 4.64 
B) -4.66 
C) 7.83 
D) 2.25

Question 7

Periodic sampling is observing the output of a process at random intervals.

Accepted Answer

A) True 
 B)False

Question 8

A bank officer wishes to study how many customers write bad checks.To accomplish this,the officer randomly selects a weekly sample of 100 checking accounts and records the number that wrote bad checks.The numbers of customers who wrote bad checks in 20 consecutive weekly samples of 100 cardholders are,respectively,1,4,9,0,4,6,0,3,8,5,3,5,2,9,4,4,3,6,4,and 0.Find the appropriate center line.

Accepted Answer

A) .08 
B) .01 
C) .09 
D) .04 
A) .08 
B) .01 
C) .09 
D) .04

Question 9

A control chart on which subgroup means are plotted versus time is a(n)_________ chart.

Accepted Answer

A)  $\overline { \mathrm { X } }$ 
B) R 
C) p 
D) C 
A)  $\overline { \mathrm { X } }$ 
B) R 
C) p 
D) C

Question 10

If $\overline { \mathrm { X } }$
And R charts are used to control a manufacturing process,an ______ chart is analyzed first and brought into a state of statistical control before preparing the _______ chart.

Accepted Answer

A) R,
$\overline { \mathrm { X } }$ 
B)  $\overline { \mathrm { X } }$ 
A) R,
$\overline { \mathrm { X } }$ 
B)  $\overline { \mathrm { X } }$

Question 11

For a manufacturing process, $\overline { \overline  X }$ 
= 10 inches, $\overline { \mathrm { R } }$
= )4 inches,and the subgroup sample size is 6 units.Calculate the standard control limits for the $\bar { X }$
Chart.

Accepted Answer

A) 9.526 and 10.474 
B) 9.769 and 10.231 
C) 9.807 and 10.193 
D) 9.484 and 10.516 
E) 8.80 and 11.20 
A) 9.526 and 10.474 
B) 9.769 and 10.231 
C) 9.807 and 10.193 
D) 9.484 and 10.516 
E) 8.80 and 11.20

Question 12

How well a process is able to meet the requirements set forth by the process design is called the quality of _____________.

Accepted Answer

A) performance 
B) conformance 
C) design 
D) control 
A) performance 
B) conformance 
C) design 
D) control

Question 13

Among other quality measures,the quality of an electronic component used in manufacturing stereo speakers is monitored with a control chart.In the last 25 days,daily samples of 60 units resulted in the following number of defective units per sample: 8,4,3,7,6,2,5,3,1,0,7,4,2,0,1,6,2,4,3,1,2,8,5,6,and 0.Determine the appropriate upper and lower control limits for this process.

Accepted Answer

A) [.029,.091] 
B) [.056,.064] 
C) [0,.152] 
D) [0,.202] 
A) [.029,.091] 
B) [.056,.064] 
C) [0,.152] 
D) [0,.202]

Question 14

If $\overline { \overline { X } }$

= 16.1, $\bar { R }$
= )03,and n = 6,calculate the natural tolerance limits.

Accepted Answer

A) [16.065,16.135] 
B) [16.088,16.112] 
C) [15.745,16.455] 
D) [16.055,16.145] 
A) [16.065,16.135] 
B) [16.088,16.112] 
C) [15.745,16.455] 
D) [16.055,16.145]

Question 15

A manufacturer of windows produces one type that has a plastic coating.The specification limits for the plastic coating are 30 and 70.From time to time the plastic coating can become uneven.Therefore,in order to keep the coating as even as possible,thickness measurements are periodically taken at four different locations on the window.15 subgroups were observed,each consisting of four thickness measurements,with the following results: mean of the means = $\overline {\overline{ x } }$

= 50.05,and average range = 8.85.Calculate the control limits for the X-bar chart.

Accepted Answer

A) [41.2,58.9] 
B) [48.1,52.0] 
C) [43.6,56.5] 
D) [29.9,70.2] 
A) [41.2,58.9] 
B) [48.1,52.0] 
C) [43.6,56.5] 
D) [29.9,70.2]

In 25 samples of 100 units each,75 units were found to be defective.Find the appropriate UCL and LCL for the p chart.

Sources of process variations that are inherent to the process design are called ___________ causes of variation.

Common causes of process variation:

Periodic sampling is observing the output of a process at random intervals.

A control chart on which subgroup means are plotted versus time is a(n)_________ chart.

If $\overline { \mathrm { X } }$ And R charts are used to control a manufacturing process,an chart is analyzed first and brought into a state of statistical control before preparing the _ chart.

For a manufacturing process, $\overline { \overline X }$ = 10 inches, $\overline { \mathrm { R } }$ = )4 inches,and the subgroup sample size is 6 units.Calculate the standard control limits for the $\bar { X }$ Chart.

How well a process is able to meet the requirements set forth by the process design is called the quality of _____________.

If $\overline { \overline { X } }$ = 16.1, $\bar { R }$ = )03,and n = 6,calculate the natural tolerance limits.

Statistical Inferences for Population Variances

Experimental Design and Analysis of Variance

Chi-Square Tests

Simple Linear Regression Analysis

Multiple Regression and Model Building

Time Series Forecasting and Index Numbers

Nonparametric Methods

Decision Theory

Filters

Exam 17: Process Improvement Using Control Charts

In 25 samples of 100 units each,75 units were found to be defective.Find the appropriate UCL and LCL for the p chart.

Sources of process variations that are inherent to the process design are called ___________ causes of variation.

Common causes of process variation:

Periodic sampling is observing the output of a process at random intervals.

A control chart on which subgroup means are plotted versus time is a(n)_________ chart.

If X‾\overline { \mathrm { X } }X And R charts are used to control a manufacturing process,an ______ chart is analyzed first and brought into a state of statistical control before preparing the _______ chart.

For a manufacturing process, X‾‾\overline { \overline X }X = 10 inches, R‾\overline { \mathrm { R } }R = )4 inches,and the subgroup sample size is 6 units.Calculate the standard control limits for the Xˉ\bar { X }Xˉ Chart.

How well a process is able to meet the requirements set forth by the process design is called the quality of _____________.

If X‾‾\overline { \overline { X } }X = 16.1, Rˉ\bar { R }Rˉ = )03,and n = 6,calculate the natural tolerance limits.

Statistical Inferences for Population Variances

Experimental Design and Analysis of Variance

Chi-Square Tests

Simple Linear Regression Analysis

Multiple Regression and Model Building

Time Series Forecasting and Index Numbers

Nonparametric Methods

Decision Theory

Filters

If $\overline { \mathrm { X } }$ And R charts are used to control a manufacturing process,an chart is analyzed first and brought into a state of statistical control before preparing the _ chart.

For a manufacturing process, $\overline { \overline X }$ = 10 inches, $\overline { \mathrm { R } }$ = )4 inches,and the subgroup sample size is 6 units.Calculate the standard control limits for the $\bar { X }$ Chart.

If $\overline { \overline { X } }$ = 16.1, $\bar { R }$ = )03,and n = 6,calculate the natural tolerance limits.