21) Floyd Electric is fabricating flanges for a new electrical motor. The flange is to be 25
millimeters in diameter with an upper tolerance limit of 26.5 millimeters and a lower tolerance
limit of 23.5 millimeters. Bill Floyd took a sample consisting of ten flanges, measured the
diameter and recorded the observations in the table.
25.69
25.58
24.78
24.94
24.87
24.63
25.70
25.52
24.95
24.91
What is Floyd Electric’s process standard deviation?
A) 0.15
B) 0.17
C) 0.42
D) 0.39
22) Floyd Electric is fabricating flanges for a new electrical motor. The flange is to be 25
millimeters in diameter with an upper tolerance limit of 26.5 millimeters and a lower tolerance
limit of 23.5 millimeters. Bill Floyd took a sample consisting of ten flanges, measured the
diameter and recorded the observations in the table.
25.69
25.58
24.78
24.94
24.87
24.63
25.70
25.52
24.95
24.91
What is Floyd Electric’s process capability index?
A) 1.08
B) 1.33
C) 1.42
D) 1.66
16
23) Floyd Electric is fabricating flanges for a new electrical motor. The flange is to be 25
millimeters in diameter with an upper tolerance limit of 26.5 millimeters and a lower tolerance
limit of 23.5 millimeters. Bill Floyd took a sample consisting of ten flanges, measured the
diameter and recorded the observations in the table. He has heard discussion of 6 sigma in the
business news recently and would like to join the club.
25.69
25.58
24.78
24.94
24.87
24.63
25.70
25.52
24.95
24.91
What percentage decrease in process standard deviation would be required for Floyd Electric to
achieve 6-sigma process capability? Assume that his process mean remains where it is.
A) 36%
B) 40%
C) 46%
D) 58%
24) A housekeeping supervisor inspects rooms after the staff has cleaned them and compares
their staff’s performance against a checklist of items that should be cleaned, replaced, etc.,
according to standard operating procedure at the hotel. Over the past week she finds three rooms
that have cleaning mistakes out of the 140 rooms she has inspected. How many additional rooms
should she sample to establish an average fraction defective for the p chart she would like to
make to monitor this process?
A) 78
B) 93
C) 108
D) 133
17
25) The probability of rejecting a lot with quality better than the acceptable quality level is:
A) the lot tolerance percent defective.
B) the lot tolerance percent acceptable.
C) the consumer’s risk.
D) the producer’s risk.
26) Taguchi defines quality in terms of:
A) parts per million.
B) losses.
C) lot tolerance percent defective.
D) acceptable quality levels.
27) The ability of a non-centered process to meet certain quality standards is measured by its
________.
18
28) ________ measures refer to the presence or absence of a particular characteristic.
29) The probability of accepting a lot with worse quality than the lot tolerance percent defective
level is ________.
19
30) An airline wants to monitor the performance of their baggage handling crew on the daily
flight from Oklahoma City to Dallas that is always filled to its 140 passenger capacity. They
track the number of passengers that lose bags each flight for a two-week period. The data are
displayed in the following table. Determine control limits for the appropriate chart and indicate
any points that are out of control.
Day #
# Bags Lost
1
3
2
4
3
3
4
2
5
5
6
7
7
6
8
8
9
1
10
7
11
6
12
2
13
1
14
7
20
21
31) A hot tub manufacturer wants the thermostat to control water temperature to within one
degree when set at 130 degrees Fahrenheit. They randomly select 10 hot tubs, set the thermostats
to 130, and record the following data with an infrared thermometer that has recently been
calibrated.
Temp
129.9
129.7
130.2
129.7
129.8
130
129.6
131
130.3
129.8
What is their process capability?
32) Floyd Electric is fabricating flanges for a new electrical motor. The flange is to be 25
millimeters in diameter with an upper tolerance limit of 26.5 millimeters and a lower tolerance
limit of 23.5 millimeters. Bill Floyd took a sample consisting of ten flanges, measured the
diameter and recorded the observations in the table.
25.69
25.58
24.78
24.94
24.87
24.63
25.70
25.52
24.95
24.91
What is Floyd Electric’s process capability?
23
33) The fill size for a small bag of peanuts distributed by a popular airline is 50 grams. The
producer wishes to set up a set of control charts for this process and collects the data shown in
the table. Develop the proper statistical quality control charts. Is the process in control?
Sample
Item #1
Item #2
Item #3
Item #4
Sum
1
54.5
54.3
53.8
50.4
213.0
2
50.6
53.5
53.2
54.9
212.3
3
51.1
54.3
50.4
50.7
206.6
4
52.7
52.1
51.3
51.0
207.2
5
51.7
51.2
54.7
54.3
211.8
6
51.1
51.5
54.7
50.4
207.7
7
54.0
52.3
54.7
51.4
212.4
8
53.2
50.4
53.4
51.4
208.4
9
51.9
50.2
50.2
52.9
205.1
1
2
3
4
5
6
7
8
9
24
25
34) A cell phone manufacturer inspects the video display on each color phone to verify that the
screen can display all colors with the brilliance their customers have come to expect. Each phone
is turned on, run through a self-test procedure, and classified as either acceptable or unacceptable
based on test performance. The production team takes a sample of 350 phones and finds one with
a defective display. How many additional phones should they sample to establish an average
fraction defective for their statistical quality control initiative?
35) A tailor decides to use Taguchi’s quality loss function to analyze his shirt making process.
Knowing it to be parabolic in shape and of the form L(y) = k(y – t)2 where t is the target, y is the
actual measurement, and k is the process constant, the tailor decides to use a recent customer
order to calculate his process parameters. He takes the custom shirt and measures the collar,
which was requested to have a 17.5″ collar but actually has a 17.75″ collar. The customer notices
the difference and demands a 50% reduction in the price of the shirt, which cost the tailor $45 to
make. Instead of selling the shirt for $175, the tailor will reduce his price to $87.50. What is the
tailor’s process constant for a silk shirt?
26
Learning Objective 5-5
1) ISO 9001:2008 can be used by both manufacturing and service companies.
2) One international standard for managing quality across the supply chain is:
A) ISO 9000.
B) ISO 14000.
C) AQL.
D) LTPD.
3) ________ is a family of standards, developed by the International Organization for
Standardization, representing an international consensus on good quality management practices.
27
4) Describe the ISO 9000 family of standards, including the objectives and process of becoming
certified.