6

Pretest

Directions: Identify the correct answer for each item. Write only the letter of your

choice.

1. Out of 250 students, 98 owned a laptop. What is the population proportion of the

students who owned laptop?

A. 0.39 C. 0.98

B. 0.61 D. 2.50

2. If the value of population proportion is 3/5, what is the value of q?

A. 0.30 C. 0.50

B. 0.40 D. 0.60

3. Is z-test applicable for the following given? Hypothesis test on population

proportion; n = 121, p = 0.11

A. Yes B. No C. Maybe D. Cannot be determined

4. Is z-test applicable in the following given? Hypothesis test on population proportion;

n = 17, q = 0.85

A. Yes B. No C. Maybe D. Cannot be determined

For no. 5-10

Ships arriving in Port of Manila are inspected by Customs officials for

contaminated cargo. Eighteen percent of the ships arriving last year contained cargo

that was contaminated. A random selection of 40 ships in the current year included 4

that had contaminated cargo. Does the data suggest that the proportion of ships

arriving in the port with contaminated cargoes has decreased this year? Use =0.01.

5. Which of the following is a correct null hypothesis?

A. H0: p = 0.18 C. H0: p > 0.18

B. H0: p 0.18 D. H0: p < 0.18

6. Which of the following is a correct alternative hypothesis?

A. H1: p = 0.18 C. H1: p > 0.18

B. H1: p 0.18 D. H1: p < 0.18

7. What is the population proportion?

A. 0.01 C. 0.20

B. 0.18 D. 0.40

8. What is the value of q?

A. 0.60 C. 0.80

B. 0.82 D. 0.99

9. Is z-test applicable in this problem?

A. yes, because np is greater than 5

B. yes, because nq is greater than 5

C. yes, because np and nq are both greater than 5

D. yes, because np and nq are both less than 5

10. Which of the following rejection region is applicable to the problem?

A. z > 2.33 C. z > 2.33

B.z < 2.33 D. z < 2.33

LOOKING BACK

the five essential steps in testing hypothesis.

1.

2.

3.

4.

5.

Activity 1

Directions: Which of the following statements is/are true about the use of z-test for

population proportion.

1. np and nq are both greater than 5.

2. np must be greater than 5.

3. nq must be less than 5.

4. Either np or nq must be less than 5.

5. z-test can be used regardless of the value of np and nq.

Activity 2

Directions: Identify if z-test is applicable for each the following sets of information.

Write A if applicable and N if not applicable.

1. Hypothesis test on population proportion; n = 8, p = 0.12

2. Hypothesis test on population proportion; n = 20, q = 0.95

3. Hypothesis test on population proportion; n = 50, p = 0.5

4. Hypothesis test on population proportion; n = 130, q = 0.65

5. Hypothesis test on population proportion; n = 18, q = 0.38

CHECKING YOUR UNDERSTANDING

Directions: Read each problem. Write the null and alternative hypotheses and identify

the rejection region.

1. A telephone company claims that 80% of young adults in Manila are using their

cellphones to connect to the internet. In a random sample of 130 young adults, 110

say that they use their phones to access the internet. Is there enough evidence to

support the said claim? Use = 0.01.

2. A Tutorial Center claims that more than 75% of their customers are very satisfied

with their services. One hundred were surveyed using random sampling and it was

found out that 83 are very satisfied. Based on these results, should we accept or reject

the company's claim? Use a 0.05 level of significance.

POST TEST

Directions: Identify the correct answer for each item. Write only the letter of your

choice.

1. Out of 250 students, 98 owned a laptop. What is the population proportion of the

students who do not owned laptop?

A. 0.39 C. 0.98

B. 0.61 D. 2.50

2. If the value of population proportion is 0.25, what is the value of q?

A. 1/4 C. 1/2

B. 1/3 D. 3/4

3. Is z-test applicable in the following given? Hypothesis test on population

proportion; n = 121, p = 0.98

A. Yes B. No C. Maybe D. Cannot be determined

4. Is z-test applicable in the following given? Hypothesis test on population proportion;

n = 17, q = 0.50

A. Yes B. No C. Maybe D. Cannot be determined

For no. 5-10

Ships arriving in Port of Manila are inspected by Customs officials for

contaminated cargo. Twenty percent of the ships arriving last year contained cargo

that was contaminated. A random selection of 40 ships in the current year included

10 that had contaminated cargo. Does the data suggest that the proportion of ships

arriving in the port with contaminated cargoes has increased this year? Use =0.05.

5. Which of the following is a correct null hypothesis?

A. H0: p = 0.20 C. H0: p > 0.20

B. H0: p 0.20 D. H0: p < 0.20

6. Which of the following is a correct alternative hypothesis?

A. H1: p = 0.20 C. H1: p > 0.20

B. H1: p 0.20 D. H1: p < 0.20

7. What is the population proportion?

A. 0.01 C. 0.20

B. 0.18 D. 0.40

8. What is the value of q?

A. 0.60 C. 0.80

B. 0.82 D. 0.99

9. Is z-test applicable for this problem?

A. yes, because np is greater than 5

B. yes, because nq is greater than 5

C. yes, because np and nq are both greater than 5

D. yes, because np and nq are both less than 5

10. Which of the following rejection region is applicable for this problem?

A. z > 1.645 C. z > 1.645

B. z < 1.645 D. z < 1.645