San Jose State University
Charles W. Davidson College of Engineering
E 10 – Introduction to Engineering
Engineering Applications Using Formulas and Charts/Graphs
All exercises should be performed in groups of two, so find a partner. Print out the Excel sheet,
codes and answers, for each exercise. You should be able to fit more than one exercise per sheet.
Make sure all codes in Excel (spreadsheet cells) and answers are clearly labeled. Include your
names and section on each print out.
Exercise 1
An engineering student took five courses in Spring semester of year 2007. The credit hours and the
grades for these courses are listed below,
Course
Credit Hours (xi)
Grade
1
3
B
2
4
C+
3
5
A-
4
3
B+
5
3
D
Calculate the grade point average (formula given below) for the semester of the student. Note that the
grade point associated with each letter grade (per each credit hour) is assigned as follows:
Grade
Points
(yi)
A
4.0
A3.7
B+
3.3
B
3.00
B2.7
C+
2.3
C
2.00
C1.7
D+
1.3
D
1.00
D0.7
F
0.00
n
Grade Point Average 
x
i 1
n
i
x
i 1
yi
, n  number of courses
i
where xi is the credit hours of course i and yi is the point associated with the grade for course i.
Exercise 2
The following information on inventory of certain parts of a manufacturing company is available: The
first column displays the identification numbers of the parts manufactured; the second column presents
the number of units on hand available for the corresponding part; the third column gives the per-unit
manufacturing cost of the corresponding part; the fourth column gives the unit sales price for the
corresponding part. The company has the following simple inventory policy. When the current stock
level (i.e., the number of units in the current inventory) of a part falls below a threshold, called the
minimum stock level, the company will order the part from its suppliers. The order quantity (i.e., the
amount of units ordered) for the part plus the current stock level should be to equal to the maximum
number of units that can be held in inventory, called the maximum stock level. The total order cost is
the sum of the order costs for all parts that must be ordered.
Item Part
Quantity
Number
On Hand
19165
35
19166
46
19167
89
19168
12
19169
53
19170
6
19171
22
19172
31
19173
100
19174
19
19175
77
19176
33
Minimum Stock Level
Maximum Stock Level
Per Unit
Cost
$1.21
$0.35
$3.55
$2.67
$2.25
$1.95
$1.55
$5.50
$3.95
$4.25
$0.65
$1.19
30
100
Per Unit
Price
$1.65
$0.49
$4.80
$3.60
$3.00
$2.65
$2.10
$7.45
$5.35
$5.75
$0.85
$1.60
Use appropriate EXCEL formulas/functions to answer the following questions:
1. What is the greatest quantity on hand among all the parts stocked in the inventory?
2. What is the average quantity on hand across all parts?
3. What is the total dollar amount tied up in inventory, in terms of cost?
4. What is the average inventory cost per unit inventoried?
5. How many parts have a unit price that is greater than $2.00?
6. If the quantity on hand is less than 30, then display an order quantity (in a column) of
100 minus the quantity on hand for the item (to bring the stock level up to 100 units
of item). Otherwise the quantity ordered is zero.
7. Use the VLOOKUP function of Microsoft Excel to display the unit price for the
part with the identification number of 19170.
Exercise 3
Preventing fatigue crack propagation in aircraft structures is an important element of aircraft safety. An
engineering study to investigate fatigue crack in n = 9 cyclically loaded wing boxes reported the
following crack lengths (in mm): 2.13, 2.96, 3.02, 1.82, 1.15, 1.37, 2.04, 2.47, 2.60. Calculate the
sample mean (i.e., the average of the lengths) and sample standard deviation (as a measure of
variability of the lengths) by using the formulas given below and then verifying the answers by
entering Microsoft Excel statistical functions Average and Stdev, respectively. Interpret them.
Data Observations: x1 , x 2 ,....., x n
n
Sample mean: x 
 xi
i 1
n
n
Sample Variance: s 2 
 (x
 x)2
i 1
n 1
and Sample Standard Deviation: s  s 2
For exercises 4 to 7, use a chart/graph to answer the questions, all charts must have a title with
x-axis and y-axis labeled appropriately.
Exercise 4
The following information on structural defects in a random sample of automobile doors is obtained:
Types of Defects
Dents
Pits
Parts assembled out of sequence
Parts under trimmed
Missing holes/slots
Parts not lubricated
Parts out of contour
Parts not deburred
Number of Occurrences
4
4
6
21
8
5
30
3
1) Construct an appropriate chart to help visualize how frequently different types of defects occur.
2) Construct an appropriate chart to see the percentage of defects of each of the different types with
respect to the total number of defects.
Exercise 5
The net energy consumption (in billions of kilowatt hours) for countries in Asia in 2003 is shown
below. Construct a compact summary of this data.
Countries
Afghanistan
Australia
Bangladesh
Burma
China
Hong Kong
India
Indonesia
Japan
Korea, North
Korea, South
Laos
Malaysia
Mongolia
Nepal
New Zealand
Pakistan
Phillipines
Singapore
Sri Lanka
Taiwan
Thailand
Vietnam
Billions of Kilowatt Hours
1.04
200.66
16.20
6.88
1,671.23
38.43
519.04
101.80
946.27
17.43
303.33
3.30
73.63
2.91
2.30
37.03
71.54
44.48
30.89
6.80
154.34
107.34
36.92
1) Is the distribution of energy consumption for countries in Asia symmetric? Use a histogram to
answer the question.
2) Which countries consume the most energy, and which consume the least?
Exercise 6
Concentration readings (in grams per liter) on a chemical process were made every two hours. Some of
these data follow (left to right, then down).
17.0
16.7
17.1
17.5
17.6
16.6
17.4
17.4
18.1
17.5
16.3
17.2
17.4
17.5
16.5
16.1
17.4
17.5
17.4
17.8
17.1
17.4
17.4
17.4
17.3
16.9
17.0
17.6
17.1
17.3
16.8
17.3
17.4
17.6
17.1
17.4
17.2
17.3
17.7
17.4
17.1
17.4
17.0
17.4
16.9
17.0
16.8
17.8
17.8
17.3
1) Construct a plot to see how the process progressed over time. Do you see any trend in
concentration readings over time from the plot?
2) Predict what the next reading in 2 hours may be.
Exercise 7
The following table presents the highway gasoline mileage performance and engine displacement for
Daimler-Chrysler vehicles for model year 2005 (Source: Environmental Protection Agency).
Carline
300C/SRT-8
Caravan 2WD
Crossfire Roadster
Dakota Pickup 2WD
Dakota Pickup 4WD
Durango 2WD
Grand Cherokee 2WD
Grand Cherokee 4WD
Liberty/Cherokee 2WD
Liberty/Cherokee 4WD
Neon/SRT-4/SX 2.0
Pacifica 2WD
Pacifica AWD
PT Cruiser
Ram 1500 Pickup 2WD
Ram 1500 Pickup 4WD
Sebring 4-DR
Stratus 4-DR
Town & Country 2WD
Viper Convertible
Wrangler/TJ 4WD
Engine Displacement
(in3)
215
201
196
226
226
348
226
348
148
226
122
215
215
148
500
348
165
148
148
500
148
Highway Miles per
Gallon (MPG)
30.8
32.5
35.4
28.1
24.4
24.1
28.5
24.2
32.8
28
41.3
30.0
28.2
34.1
18.7
20.3
35.1
37.9
33.8
25.9
26.9
1) Construct a plot to see if there is a relationship between the two variables: displacement and miles
per gallon. Fit a straight line relating highway miles per gallon (y) to engine displacement (x) in
cubic inches.
2) What kind of relationship do the two variables have? Is it positive or negative? Is the correlation
strong or weak?