1.
A company has recorded data on the weekly sales for its product ( y ) and the unit price of the competitor’s product ( x ). The data resulting from a random sample of 7 weeks follows.
Use Excel’s Regression Tool to answer the following questions.
Week Price Sales
1 .33 20
2 .25 14
3 .44 22
4 .40 21
5 .35 16
6 .39 19
7 .29 15
a. What is the estimated regression equation?
Perform x and y are related. Use
α
=
0.05.
Perform x and y are related. Use
α
=
0.05.
d. Find and interpret the coefficient of determination.
2.
One thousand managers with degrees in business administration indicated their fields of concentration as shown below.
Major Top Management Middle Management TOTAL
Management 300 200 500
Marketing 200 0 200
Accounting 100 200 300 of concentration.
3.
Members of a focus group stated their preferences between three possible slogans. The results follow. Use Excel to test at
α
= .05 to determine any difference in preference among the three slogans H
0
: p
A
= p
B
= p
C
= 1
3
.
1

Slogan Preferences
A A C C B
C B B A A
B C A B C
C C C B B
C B C C A
A A C A B
4.
Below you are given ages that were obtained by taking a random sample of 9 undergraduate students.
19 22 23 19 21 22 19 23 21
Use Excel to determine an interval estimate for the mean of the population at a 99% confidence level. Interpret your results.
5.
Guitars R. US has three stores located in three different areas. Random samples of the sales of the three stores (in $1000) are shown below.
Store 1 Store 2 Store
80 85 79
75 86 85
76 81 88
89 80
At a .05 level of significance, use Excel to test to see if there is a significant difference in the average sales of the three stores.
6.
A group of young businesswomen wish to open a high fashion boutique in a vacant
store, but only if the average income of households in the area is more than $45,000.
A random sample of 9 households showed the following results.
$48,000 $44,000 $46,000 $45,000
$43,000 $47,000 $46,000 $42,000 $44,000
Use the statistical techniques in Excel to advise the group on whether or not they should locate the boutique in this store (i.e., test H
0
:
≤
45000 ) . Use a .05 level of significance.
2

7.
A manufacturer claims that at least 40% of its customers use coupons ( H
0
: p
≥
0 .
4 ). A study of 25 customers is undertaken to test that claim. The results of the study follow. yes no no yes yes no yes no no yes no no no no yes no no no no yes no no yes no yes
At a .05 level of significance, use Excel to test the manufacturer’s claim.
8.
The sponsors of televisions shows targeted at the market of 5 – 8 year olds want to test the hypothesis that children watch television at most 20 hours per week ( H
0
:
≤
20 ). A market research firm conducted a random sample of 30 children in this age group. The resulting data follows:
19.5 29.7 17.5
14.6 10.1 12.5
22.2 19.8 11.8
27.4 26.5 16.1
27.0 15.6 17.1
10.4
18.2
19.0
21.7
19.2
19.4
19.1
27.7
20.6
20.1
18.4
30.9
25.3
32.9
17.7
At a .10 level of significance, use Excel to test the sponsors’ hypothesis.
9.
A manufacturing company wants to estimate the difference in the proportion of defective parts between two machines. Independent random samples of parts are taken from both machines. The results follow. Use Excel to estimate the difference in the proportion of defective parts between two machines with a 99% level of confidence.
Machine 1 yes Yes no no Yes no no No no no Yes no no No no no No no no No no no Yes no yes no yes no no no no no
Machine 2 no yes no no no yes no no no no no no no no no no
3

no No no no No no
10.
Independent samples of commuters are taken from two cities. The following data represents the time (in minutes) to drive to work. Use Excel to determine whether the average commuting times are significantly different between the two cities. Use
α
= .05.
City A no yes yes no no no
City B
15.25 40.25 12.75 48.75
25.50 50.00 12.50 12.25
18.75 45.00 15.50 10.00
60.25 16.75 22.75 42.00
10.50 18.75 38.75 42.50
10.50 28.50 45.00 12.25
35.75 30.00
4