16)
Suppose Burger King has run a major advertising campaign in the hopes of increasing monthly
sales. To investigate the effectiveness of this campaign, Burger King randomly selected six
restaurants and recorded the monthly sales before and after the advertising. The following data
represents these sales figures in thousands of dollars.
Restaurant 1
2
3
4
5
6
After
$123
$122
$145
$156
$160
$134
Before
$107
$110
$143
$168
$145
$125
If Population 1 is defined as sales after the advertising campaign and Population 2 is defined as
sales before the advertising campaign, the standard deviation of the matched

pair differences is
________.
16)
A)
15.72
B)
7.46
C)
12.31
D)
10.58
17)
Two real estate companies, Century 21 and RE/MAX, compete with one another in a local market.
The manager of the Century 21 office would like to advertise that homes listed with RE/MAX
average more than 10 days on the market when compared to homes listed with his company. The
following data shows the sample size and average number of days on the market for the two
companies along with the population standard deviations.
Century 21
RE/MAX
Sample mean
122 days
144 days
Sample size
36
30
Population standard deviation
32 days
35 days
If Population 1 is defined as RE/MAX and Population 2 is defined as Century 21, the 80%
confidence interval for the difference in population means is ________.
17)
TRUE/FALSE.
Write 'T' if the statement is true and 'F' if the statement is false.
18)
When performing a hypothesis test comparing two population means, we need to assign
Population 1 to the larger sample mean and Population 2 to the smaller sample mean.
18)
MULTIPLE CHOICE.
Choose the one alternative that best completes the statement or answers the question.
19)
You have been assigned to test the hypothesis that the average number of hours per week that an
American works is higher than the average number of hours per week that a Swede works. The
following data summarizes the sample statistics for the number of hours worked per week for
workers in each country. Assume that the population variances are unequal.
American
Swede
Sample mean
32.7 hours
28.2 hours
Sample size
15
12
Sample standard deviation
5.1 hours
6.0 hours
If Population 1 is defined as American workers and Population 2 is defined as Swedish workers,
the degrees of freedom for this hypothesis test are ________.
19)
5
20)
The Canadian government would like to test the hypothesis that the average hourly wage for men
is more than $2.00 higher than the average hourly wage for women. The following data
summarizes the sample statistics for hourly wages for men and women.
Men
Women
Sample mean
$25.40
$21.20
Sample size
20
18
Sample standard deviation
$6.20
$5.90
If Population 1 is defined as men and Population 2 is defined as women, the test statistic for this
hypothesis test would be ________.
20)