______ 1. A null hypothesis can only be rejected at the 5% significance if and only if A. The null hypothesis does not make sense. B. The alternate hypothesis is wrong at 5% of the time C. At 95% confidence interval includes the hypothesized value of the parameter. D. A 95% confidence interval does not include the hypothesized value of the parameter.

I. Direction: Choose the letter of the correct or best answer. Write the CAPITAL LETTERS of your
answer before the number. If the answer is not among the choices, write E before the number.
______ 1. A null hypothesis can only be rejected at the 5% significance if and only if
A. The null hypothesis does not make sense.
B. The alternate hypothesis is wrong at 5% of the time
C. At 95% confidence interval includes the hypothesized value of the parameter.
D. A 95% confidence interval does not include the hypothesized value of the parameter.
______ 2. Consider the null hypothesis ?0: ? = 0.18 indicates that the proportion of fat content of the
burgers being sold in the canteen is 18% or less. Which of the following is true about the type I and type
II error?
A. A type I error occurs when the actual proportion is about 18% or more, but the null
hypothesis is rejected. A type II error when the actual proportion is about18% or less but
the null hypothesis is rejected.
B. A type I error occurs when the actual proportion is about 18% or less, but the null
hypothesis is rejected. A type II error occurs when the actual proportion is about 18% or
more, but the null hypothesis is accepted.
C. A type I error occurs when the actual proportion is about 18% or more, but the null
hypothesis is accepted. A type II error occurs when the actual proportion is about 18% o
less, but the null hypothesis is rejected.
D. A type I error occurs when the actual proportion is about 18%, and the null hypothesis is
rejected. A type II error occurs when the actual proportion is about 18% or less, but the
null hypothesis is rejected.
For numbers 3 to 8, refer to the given situation: Erwin believes that with his current internet
subscription, he can download a 750 mb movie in just 14 minutes. In order to test his own claim,
he took a random sample of 10 downloading time obtained a mean of 14.75 minutes with
standard deviation of 1.75 minutes.
______ 3. What are the null and alternate hypotheses?
A. ??: ? = 14; ?0: ? ≠ 14
B. ??:? ≠ 14; ?0: ? = 14
C. ??:? < 14; ?0: ? ≠ 14
D. ??:? < 14; ?0: ? = 14
______ 4. What type of test is appropriate for the situation?
A. ? − ???? B. ? − ???? C. ? − ???? D. ? − ????
______ 5. What value of the test statistic?
A. 1.79 B. -1.79 C. 1.645 D. -1.64
______ 6. Which of the following is the critical value at ? = 0.05?
A. ±1.645 B. ±1.96 C. ±1.833 D. ±2.262
______ 7. What is the decision in the test with ? = 0.05 level of significance?
A. Accept the null hypothesis.
B. Reject the null hypothesis
C. The given information is not enough to make any conclusion
D. Cannot be determine.
______ 8. What is the ? − ????? for the two tailed hypothesis test with test statistics of ? = 1.93?
A. 0.0563 B. 0.0536 C. 0.5036 D. 0.5306
For items 9 to 13, refer to the given situation: Hauz of Gaz claims that more than two-thirds of
the houses in a certain subdivision use their brand. Is there a reason to doubt this claim if 25
out of a random sample of 40 houses in the subdivision use the company’s brand? Test the
claim at 0.01 level of significance.
______ 9. What are the null and alternate hypotheses?
A. ??: ? = 0.67; ?0: ? ≠ 0.67 C. ??: ? < 0.67; ?0: ? ≠ 0.67
B. ??: ? ≠ 0.67; ?0: ? = 0.67 D. ??: ? < 0.67; ?0: ? = 0.67
______ 10. What type of test is appropriate for this situation?
A. ? − ???? B. ? − ???? C. ? − ???? D. ? − ????
______ 11. Which of the following are the critical values at ? = 0.05?
A. -2.33 B. 2.33 C. ±2.33 D. ±2.262
______ 12. What is the value of the test statistic?
A. 0.6053 B. 0.6503 C. -0.6053 D. -0.6503
______ 13. Based on the result on the comparison between critical and computed value, what can be
concluded?
A. There is enough evidence to reject the claim that more than two-thirds of the houses
in the subdivision use Hauz of Gaz brand.
B. There is not enough evidence to reject the claim that more than two-thirds of the
houses in the subdivision use Hauz of Gaz brand.
C. Accept the null hypothesis.
D. The given information is not enough to make any conclusion.
For numbers 14 to 17: the maximum oxygen uptake of healthy women is assumed to be thirty.
Thirty women in a mountain city were measured, and the following values were found: mean is
33.3, and the standard deviation is 12.14. Can we hypothesized at 0.05 level of significance that
these women have a higher than thirty oxygen uptake?
______ 14. What statistic to be used in testing the hypotheses?
A. Z-test for single mean C. T-test for two means
B. T-test for paired difference D. T-test for single mean
______ 15. What is the computed test statistics?
A. 1.489 B. 0.00 C. -1.489 D. 15.00
______ 16. What is the critical value?
A. 1.645 B. 1.96 C. 1.699 D. 1.697
______ 17. What would be your decision concerning the null hypothesis?
A. Reject the null hypothesis C. Failed to reject the null hypothesis
B. There is insufficient data to make a decision D. Either A or B
For numbers 18 to 21: A study was conducted using 50 undergraduates at a large private
university who volunteered to participate in the research as partial fulfillment of a course
requirement. One of the items studied was the maximum daily amount of alcohol consumed in the
last month. Base on the data in the following table, are there differences between males and females
in the maximum amount of alcohol consumed in any one day in the past month? Use 5 % level of
significance. Assume equal variances.
Alcohol consumed Male female
Mean 8.2 5.6
Standard deviation 5.9 5.7
Number of students 20 30
______ 18. Which of the following is the appropriate alternative hypothesis?
A. There are more female participants than males
B. The amount of alcohol consumed by males is higher than the amount consumed by the
females.
C. The amount of alcohol consumed by males and females in the past month is not the
same.
D. The amount of alcohol consumed by males and females in the past month is the same.
______ 19. The pooled variance would be?
A. 134.56 B. 67.3 C. 33.408 D. 5.780
______ 20. What is the value of the test statistics?
A. 1.098 B. 1.558 C. 0.270 D. 0.776
______ 21. With ?0.025=±2.011; what would be your decision?
A. There is no sufficient data to make a decision C. Reject the null hypothesis
B. Failed to reject the null hypothesis D. Either A or B
For numbers 22 to 24 : the average length of time for the students to register for summer
classes at a certain university has been 50 minutes with a variance of 100. A new registration
procedure using computers is being tried. In a random sample of 30 students, the mean
registration time was 42 minutes. Test the hypothesis that the average length of time for
registration has been shortened due to the new system.
______ 22. What is the value of the test statistic?
A. -4.382 B. 5.014 C. 2.033 D. 1.584
______ 23. At a 0.05 level of significance, what is the critical value?
A. -2.045 B. -1.645 C. -1.96 D. -1.699
______ 24. What ca u conclude about the new system of registration?
A. There is enough evidence that the new system registration shortened the average
length of time for students to register.
B. There is insufficient evidence that the new system of registration shortened the
average length of time for students to register.
C. There is not enough data to make a conclusion
D. The new system of registration is not effective in decreasing the average length of time
for registration.
For items 25 to 26: A farmer has decided to use a new additive to grow his crops. He divided his
farm into 10 plots and kept records of the corn yield (in bushels) before and after using the
additive. The results are shown below.
PLOT 1 2 3 4 5 6 7 8 9 10
BEFORE 9 9 8 7 6 8 5 9 10 11
AFTER 10 9 9 8 7 10 6 10 10 12
You wish to test the following hypothesis at the 10 percent level of significance.
?0: ?? = 0 ?? ??: ?? ≠ 0.
______ 25. What is the value of the appropriate test statistic?
A. 2.536 B. 5.014 C. 2.033 D. 1.584
______ 26. What can you conclude about the new additive?
A. There is enough evidence that the additive is not effective in growing corns.
B. There is no difference between the yield of corn before and after applying the additive.
C. There is not enough evidence that the additive is effective in growing corn.
D. The additive has increased the yield of corn.
For items 27 to 29: A professor wants to determine whether there is a difference in the final
averages between the past two semesters. Of his business statistics classes. For a random sample
of 16 students from semester 1, the mean of the final averages was 75 with standard deviation of 4.
For a random sample of 9 students from semester 2, the mean was 73 with standard deviation of 6.
______ 27. If the final averages form semester 1 and 2 are assumed to be normally distributed with
equal variances. Which of the following is the appropriate set of hypotheses?
A. ?0: ?1 − ?2 ≤ 0 ?? ??: ?1 − ?2 > 0 C. ?0: ?1 − ?2 = 0 ?? ??: ?1 − ?2 ≠ 0
B. ?0: ?1 − ?2 ≥ 0 ?? ??: ?1 − ?2 < 0 D. ?0: ?1 − ?2 ≠ 0 ?? ??: ?1 − ?2 = 0
______ 28. What is the computed test statistics for the appropriate test?
A. ? = 1.9964 B. ? = 0.8944 C. ? = 1.0018 D. ? = 0.5009
______ 29. What is the correct decision for the appropriate test at a 0.05 level of significance when
the population variances are assumed to be equal?
A. Do not reject the null hypothesis. C. Reject the alternate hypothesis
B. Reject the null hypothesis D. Do not reject the alternate hypothesis.
______ 30. Which of the following is correct?
A. The Probability of type I error is ?
B. The probability of type two error is (1 − ?)
C. The probability of type II error is ?
D. None of the above.