1. What is meant by a population in statistics?

2. Which best describes a sample?

3. A company has 4,800 workers and surveys 160. What is the sample size?

4. What is a numerical measure describing an entire population called?

5. The average income of 75 selected households is an example of a:

6. Which method collects data from every population member?

7. A lecturer randomly draws 30 names from 300 students using a lottery. Which method is used?

8. A shop interviews every 20th customer. Which sampling method is used?

9. A college randomly selects students from each year of study. Which method is used?

10. A bank randomly selects four branches and surveys every employee in them. Which method is used?

11. A researcher surveys people who are easily available at a shopping mall. Which method is used?

12. A factory produces 12,000 bulbs and examines 250. What is the population?

13. Which is a quantitative variable?

14. Which is an example of qualitative data?

15. What is the purpose of selecting a representative sample?

16. A supermarket estimates average customer spending. What is its population of interest?

17. What is sampling error?

18. Which action helps reduce selection bias?

19. A bank has 3,000 account holders and selects 150. What percentage is sampled?

20. Which statement about sample size is generally correct?

21. A company surveys only premium customers to estimate spending among all customers. What is the main concern?

22. What is a sampling frame?

23. Which method ensures that important population subgroups are represented?

24. The number of products sold by each salesperson uses which measurement scale?

25. What is a major disadvantage of a census?

26. A company selects 45 employees from 450. What is the sampling fraction?

27. Which is an example of a population parameter?

28. Why might a business use stratified sampling?

29. A researcher analyses 220 selected customers from a database of 5,000. The 220 customers constitute the:

30. What is the relationship between a population and a sample?

31. What is the primary purpose of a confidence interval?

32. A sample of 80 customers has an average expenditure of RM250. What is the point estimate of the population mean?

33. A sample mean is 68 with a margin of error of 4. What is the lower confidence limit?

34. A confidence interval ranges from 90 to 130. What is its midpoint?

35. A confidence interval ranges from 25 to 41. What is the margin of error?

36. Which confidence level is commonly used in introductory statistics?

37. What generally happens when sample size increases, holding other factors constant?

38. Which confidence level generally produces the widest interval using the same data and method?

39. What is the estimated standard error of the sample mean when the sample standard deviation is s and sample size is n?

40. A sample standard deviation is 12 and the sample size is 36. What is the standard error?

41. A sample mean is RM350 with a margin of error of RM20. What is the upper confidence limit?

42. A sample mean is 80, the standard error is 2.5, and the critical value is 2. What is the margin of error?

43. A sample mean is 120 with a margin of error of 8. What is the confidence interval?

44. Average customer spending is RM90 with a margin of error of RM7. Which interval is correct?

45. What does a 95% confidence level mean?

46. A sample standard deviation is 24 and sample size is 64. What is the standard error?

47. A sample mean is 150, the standard error is 5, and the critical value is 1.96. What is the margin of error?

48. A sample mean is 75 with a margin of error of 6.5. What is the lower confidence limit?

49. Which distribution is commonly used to estimate a population mean when the population standard deviation is unknown and assumptions are met?

50. Which symbol commonly represents the sample proportion?

51. A sample proportion is 0.35 with a margin of error of 0.04. What is the upper confidence limit?

52. A confidence interval for average delivery time is 22 to 30 minutes. What is the best interpretation?

53. Which change generally increases the width of a confidence interval for a population mean?

54. A sample mean is 600 with a margin of error of 25. What is the total interval width?

55. A confidence interval ranges from RM720 to RM880. What is the margin of error?

56. A confidence interval for monthly profit ranges from RM18,000 to RM26,000. What is its midpoint?

57. How can a researcher generally obtain a narrower confidence interval at the same confidence level?

58. A confidence interval for waiting time is 10 to 16 minutes. Which value is outside the interval?

59. Compared with a 95% confidence interval using the same data and method, a 99% interval is generally:

60. The estimated standard error is 3.2 and the critical value is 2.5. What is the margin of error?

61. What is the main purpose of hypothesis testing?

62. Which symbol represents the null hypothesis?

63. Which symbol represents the alternative hypothesis?

64. A manufacturer claims its products have an average weight of 250 grams. Which is the appropriate null hypothesis?

65. A manager suspects that average waiting time exceeds 12 minutes. Which alternative hypothesis is appropriate?

66. Which symbol represents the significance level?

67. Which significance level is commonly used in introductory hypothesis testing?

68. A test gives a p-value of 0.03 at a significance level of 0.05. What is the decision?

69. A test gives a p-value of 0.18 at a significance level of 0.05. What is the decision?

70. What is a Type I error?

71. What is a Type II error?

72. A company tests whether average sales differ from RM8,000. Which alternative hypothesis is suitable?

73. A delivery service wants to determine whether average delivery time has decreased from 35 minutes. Which alternative hypothesis is appropriate?

74. A manufacturer tests whether its products last longer than 2,000 hours. Which test direction is appropriate?

75. A retailer investigates whether an advertising campaign changes average spending in either direction. Which test is appropriate?

76. What does a p-value measure?

77. Why should the significance level be selected before examining the test results?

78. A bank tests whether average processing time is 10 minutes. The p-value is 0.02 and α=0.01. What is the decision?

79. A test gives a p-value of 0.004 at a 5% significance level. What is the conclusion?

80. What does a significance level of 0.05 represent?

81. A company tests whether a new promotion increases sales. Which pair of hypotheses is suitable?

82. A factory tests whether its defect proportion differs from 4%. Which alternative hypothesis is correct?

83. A company concludes that a training programme improves productivity when it actually does not. Which error occurred?

84. A retailer concludes that a promotion has no statistically detectable effect when it actually increases sales. Which error may have occurred?

85. What does it mean to fail to reject the null hypothesis?

86. A business tests H0:μ=150 against H1:μ≠150. What does the alternative hypothesis mean?

87. A manager suspects average customer spending is below RM180. Which alternative hypothesis is appropriate?

88. When is a result generally considered statistically significant?

89. Why might a statistically significant result have little practical importance?

90. A test uses α=0.05α=0.05 and gives p=0.05p=0.05. Using p≤αp≤α, what is the decision?

91. A manager obtains p=0.27p=0.27 at α=0.10α=0.10. What is the correct conclusion?

92. Which sequence correctly represents hypothesis testing?

93. A company tests whether average monthly expenditure equals RM750. Which parameter is being tested?

94. A symmetric two-tailed test uses a significance level of 0.04. What significance level is allocated to each tail?

95. A company tests whether average monthly sales differ from RM25,000. The p-value is 0.03 and α=0.05α=0.05. What is the conclusion?

96. A researcher tests H0:μ=60H0:μ=60 against H1:μ>60H1:μ>60. Which test is appropriate?

97. A company tests whether average production time is less than 45 minutes. Which null hypothesis is suitable?

98. A test gives p=0.008p=0.008. At which significance levels should the null hypothesis be rejected?

99. Which change generally increases the power of a hypothesis test, holding other relevant factors constant?

100. A company tests whether average monthly sales differ from RM30,000. The p-value is 0.012 at a 5% significance level. What is the conclusion?