The mean annual sales of a company in 36 of its sales offices over the country is $23,860,000, with a standard deviation of $2,150,000. A manager quotes the annual sales of the company to be $25,000,000. Compute the p-value to test whether the sample data provide evidence to reject the executive's claim that the average annual sales are $25,000,000.

A)

0.2726

B)

0.3637

C)

0

D)

0.0007

E)

0.0014

2

If α = .01 for a two-tailed hypothesis test using the z test, the critical values are:

A)

±1.90

B)

±1.96

C)

±2.00

D)

±2.33

E)

±2.58

3

A test for the population proportion, p, uses the t distribution:

A)

if n < 30

B)

if n > 30

C)

if n = 30

D)

always

E)

never

4

I would like to test the null hypothesis that the population mean is 50 versus the alternative that it is not 50. My sample size is 6, and the sample mean is 38 with sample standard deviation of 16. At α = 0.05, I should:

A)

strongly reject the null hypothesis

B)

mildly reject the null hypothesis

C)

fail to reject the null hypothesis

D)

accept the alternative hypothesis

E)

there is insufficient information to determine

5

Suppose that n = 100, and that we want to test whether the population mean is equal to 20 versus the alternative that it is not equal to 20. The sample mean is found to be 18 and the sample standard deviation is 10. Compute the p-value for this test.

A)

0.0228

B)

0.0456

C)

0.5532

D)

1.00

E)

0

6

The proportion of defective items is not allowed to be over 15%. A buyer wants to test whether the proportion of defectives exceeds the allowable limit. The buyer takes a random sample of 100 items and finds that 19 are defective. State the null and alternative hypotheses for this test.

A)

H_{0}: p ≤ .15, H_{1}: p > .15

B)

H_{0}: p < .15, H_{1}: p > .15

C)

H_{0}: p = .15, H_{1}: p * .15

D)

H_{0}: p < .15, H_{1}: p > .15

E)

none of the above

7

The proportion of defective items is not allowed to be over 15%. A buyer wants to test whether the proportion of defectives exceeds the allowable limit. The buyer takes a random sample of 100 items and finds that 19 are defective. Find the p-value.

A)

0.3686

B)

0.1314

C)

0.2628

D)

0.8686

E)

none of the above

8

A manufacturer claims that his tires last at least 40,000 miles. A test on 25 tires reveals that the mean life of a tire is 39,750 miles, with a standard deviation of 387 miles. Compute the test statistic.

A)

t = -0.65

B)

t = 3.23

C)

t = -3.23

D)

t = 0.65

E)

none of the above

9

The average income in a certain area is assumed to be approximately $25,000. A sample of size n = 36 gives a mean of $22,000 and a sample standard deviation of $7,000. State the null and alternative hypotheses used to test whether the average income of this area is as assumed.

A)

H_{0}: μ < 25,000, H_{1}: μ ≥ 25,000

B)

H_{0}: μ = 22,000, H_{1}: μ ≠ 22,000

C)

H_{0}: μ ≤ 25,000, H_{1}: μ > 25,000

D)

H_{0}: μ ≥ 22,000, H_{1}: μ < 22,000

E)

H_{0}: μ = 25,000, H_{1}: μ ≠ 25,000

10

Given a p-value of 0.065, and using the customary α = 5%, the conclusion should be:

A)

do not reject the null hypothesis

B)

reject the null hypothesis

C)

not enough information to determine

11

A random sample of 36 items gave a sample mean of 48 and a sample standard deviation of 12. Compute the p-value to test whether or not the population mean is equal to 50.

A)

0.3413

B)

-0.4772

C)

0.1587

D)

0.6826

E)

0.3174

12

Conduct a test to determine whether or not the population proportion of voters in favor of proposal A is greater than 50%. In a random sample of 200 voters, 140 said that they were in favor of this proposal. Compute the test statistic.

A)

z = 6.17

B)

z = 19.80

C)

z = 5.66

D)

z = 7.07

E)

none of the above

To learn more about the book this website supports, please visit its Information Center.

You must be a registered user to view the premium content in this website.

If you already have a username and password, enter it below. If your textbook
came with a card and this is your first visit to this site, you can
use your registration code
to
register.