Question 1:

Loner's nursery specializes in custom-designed landscaping for residential areas. The estimated labor cost associated with a particular landscaping proposal is based on the number of plantings of trees, shrubs, and so on to be used for the project. For cost-estimating purposes, managers use two hours of labor time for the planting of a medium-sized tree. Actual times from a sample of 10 plantings during the past month follow (times in hours). (Marks 12)

1.7

1.5

2.6

2.2

2.4

2.3

2.6

3.0

1.4

2.3

With a .05 level of significance, test to see whether the mean tree-planting time differs from two hours.

a)State the null and alternative hypotheses.

b)compute the sample mean.

c)compute the sample standard deviation.

d)what is the p-value?

Question 2:

The manager of a resort in Squamish, BC, stated that the mean guest bill for a

weekend is $800 or less. A member of the hotel's accounting staff noticed that the total charges for guest bills have been increasing in recent months. The accountant will use a sample of future weekend guest bills to test the manager's claim. (Marks 6)

a)Which form of the hypotheses should be used to test the manager's claim? Explain.

Ho: 800Ho: 800Ho: =800

Ha: <800ha: >800Ha: 800

Question 3: Simon, has just begun her new job as a Manager on the sales force of a very

reputable company. In a sample of 20 sales calls it was found that she closed the contract

for an average value of 120 dollars with a standard deviation of 16dollars. Test at 5%

significance that the population mean is at least 100 dollars against the alternative that it

is less than 100 dollars. Company policy requires that new members of the sales force

must exceed an average of $100 per contract during the trial employment period.

(Marks 9)

a)Formulate the hypotheses

b)Calculate the test statistics

c)Can we conclude that Simon has met this requirement at the significance level of 95%?

Question 4: Consider the following data for two independent random samples taken from two

normal populations. (Marks 9).

Sample 1

10

7

13

7

9

8

Sample 2

8

7

8

4

6

9

a)Compute the two-sample means

b)Compute the two standard deviations

c)What is the point estimate of the difference between the two population mean?

d)What is the 90% confidence interval estimate of the difference between the two population means?

Question 5.The following data are from a completely randomized design. (Marks 18)

Treatment

Observation

A

B

C

1

162

142

126

2

142

156

122

3

165

124

138

4

145

142

140

5

148

136

150

6

174

152

128

Sample Mean

156

142

134

Sample Variance

164.4

131.2

110.4

a)Compute the sum of squares between treatments.

b)Compute the mean square between treatment

c)Compute the sum of squares due to error.

d)Compute the mean square due to error.

e)Set up the ANOVA table for this problem.

f)At the a = .05 level of significance, test whether the means for the three treatments are equal.