Solutions Manual by Norean R. Sharpe,
Richard D. De Veaux & Paul F.
Velleman – Complete Chapter Solutions
& Answer Guide
9 - answer-Sample Size (n):
81 (Bachelor's) 49 (Associates)
Sample Mean Salary (in $1,000):
60 (Bachelors) 51 (Associates)
Population Variance:
175 (Bachelors) 90 (Associates)
The following table shows sample salary information for employees with bachelor's and
associate degrees for a large company in the Southeast United States. The point estimate of the
difference between the means of the two populations is ______.
Fail to reject the null hypothesis - answer-Men:
Sample Size: 25
Sample Mean: 23
Population St. Dev: 5
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,Women
Sample Size: 30
Sample Mean: 28
Population St. Dev: 10
A recent study focused on the amount of money single men and women save monthly. The
information is summarized next. Assume that the population standard deviations are equal. At
the .01 significance level, what is the conclusion about the way women and men save?
0.0336 - answer-Manufacturer 1
n1 = 81
x1 = $15.80
o1 = $3.00
Manufacturer 2
n1 = 64
x1 = $15.00
o1 = $2.25
Use the following table to determine whether or not there is a significant difference between
the average hourly wages at two manufacturing companies. The p-value is ______.
+0.933 - answer-Product FIFO LIFO
1 ; 225 ; 221
2
,2 ; 119 ; 100
3 ; 100 ; 113
4 ; 212 ; 200
5 ; 248 ; 245
Accounting procedures allow a business to evaluate its inventory costs based on two methods:
LIFO (Last In First Out) or FIFO (First In First Out). A manufacturer evaluated its finished goods
inventory (in $000s) for five products with the LIFO and FIFO methods. To analyze the
difference, they computed (FIFO - LIFO) for each product. Based on the following results, and
testing if the LIFO method result in a lower cost of inventory than the FIFO method. What is the
value of calculated t?
The population variances are assumed equal but unknown - answer-When testing the
difference between two population means, the sample variances are pooled to estimate the
population variance when ________________.
H0: µ1 ≤ µ2 - answer-Campus Sample Size Mean Pop. St. Dev
1 ; 330 ; 33 ; 8
2 ; 310 ; 31 ; 7
The results of a mathematics placement exam at two different campuses of Mercy College
follow: What is the *null hypothesis* if we want to test the hypothesis that the mean score on
Campus 1 is higher than on Campus 2?
When two dependent samples are compared - answer-When is it appropriate to use the paired
difference t-test?
The two population standard deviations must be known. - answer-Which condition must be met
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, to conduct a test for the difference in two sample means using a z-statistic?
25 - answer-We test for a hypothesized difference between two population means: H0: ?1 = ?2.
The population standard deviations are unknown but assumed equal. The number of
observations in the first sample is 15, and 12 in the second sample. How many degrees of
freedom are associated with the critical value?
H1: µ1 > µ2 - answer-Campus Sample Size Mean Pop. St. Dev
1 ; 330 ; 33 ; 8
2 ; 310 ; 31 ; 7
The results of a mathematics placement exam at two different campuses of Mercy College
follow: What is the *alternative hypothesis* if we want to test the hypothesis that the mean
score on Campus 1 is higher than on Campus 2?
z-statistic - answer-Men:
Sample Size: 25
Sample Mean: 23
Population St. Dev: 5
Women
Sample Size: 30
Sample Mean: 28
Population St. Dev: 10
A recent study focused on the amount of money single men and women save monthly. The
information is summarized next. Assume that the population standard deviations are equal. The
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