Basic Statistics MCQs

Solved Basic Statistics MCQs with answers and explanations. Free practice questions for PPSC, FPSC, CSS and other government job exams on FreeSekho.

1. 1. Statistics is primarily concerned with:

   1. only drawing graphs
   2. only calculating percentages
   3. only collecting data
   4. collection, organization, analysis and interpretation of data ✓

2. 2. A numerical characteristic calculated from a sample is called a:

   1. Statistic ✓
   2. Population
   3. Variable
   4. Parameter

3. 3. A numerical characteristic describing an entire population is called a:

   1. Parameter ✓
   2. Statistic
   3. Class interval
   4. Frequency

4. 4. The complete set of all items under study is known as the:

   1. Sample
   2. Variable
   3. Frequency
   4. Population ✓

5. 5. A part selected from a population for investigation is called a:

   1. Class
   2. Sample ✓
   3. Census
   4. Parameter

6. 6. Data collected for the first time by the investigator are called:

   1. Primary data ✓
   2. Secondary data
   3. Grouped data
   4. Qualitative data

7. 7. Data obtained from existing records or published sources are called:

   1. Continuous data
   2. Primary data
   3. Raw data
   4. Secondary data ✓

8. 8. Data consisting of categories rather than numerical measurements are:

   1. Quantitative data
   2. Qualitative data ✓
   3. Grouped data
   4. Continuous data

9. 9. Data expressed in numbers are generally called:

   1. Qualitative data
   2. Ordinal data
   3. Quantitative data ✓
   4. Nominal data

10. 10. A variable that can take any value within an interval is:

    1. Constant
    2. Continuous variable ✓
    3. Discrete variable
    4. Nominal variable

11. 11. The number of times a value occurs is called its:

    1. Frequency ✓
    2. Range
    3. Class mark
    4. Cumulative mean

12. 12. Data arranged in ascending or descending order are called:

    1. Ordered data ✓
    2. Nominal data
    3. Bivariate data
    4. Raw data

13. 13. The difference between the largest and smallest observations is the:

    1. Mean
    2. Mode
    3. Range ✓
    4. Median

14. 14. The middle value of ordered data is the:

    1. Median ✓
    2. Mean
    3. Mode
    4. Range

15. 15. The value occurring most frequently is the:

    1. Median
    2. Mean
    3. Mode ✓
    4. Range

16. 16. The arithmetic average of observations is the:

    1. Median
    2. Mode
    3. Mean ✓
    4. Frequency

17. 17. A graph commonly used for continuous grouped data is a:

    1. Histogram ✓
    2. Pictogram
    3. Bar chart
    4. Pie chart

18. 18. A circle divided into sectors to represent proportions is a:

    1. Pie chart ✓
    2. Ogive
    3. Frequency polygon
    4. Histogram

19. 19. A table showing classes and their frequencies is called a:

    1. Parameter table
    2. Stem-and-leaf plot
    3. Scatter diagram
    4. Frequency distribution ✓

20. 20. The midpoint of a class interval is called the:

    1. Range
    2. Frequency
    3. Class mark ✓
    4. Class boundary

21. 21. A frequency obtained by successively adding frequencies is:

    1. Modal frequency
    2. Relative frequency
    3. Class frequency
    4. Cumulative frequency ✓

22. 22. Frequency divided by total frequency is called:

    1. Relative frequency ✓
    2. Class width
    3. Range
    4. Cumulative frequency

23. 23. The number of observations in a data set is denoted by:

    1. f
    2. x
    3. n ✓
    4. N

24. 24. A census studies:

    1. every member of the population ✓
    2. only grouped data
    3. only numerical data
    4. only a sample

25. 25. An observation that is unusually far from other observations is called an:

    1. Average
    2. Frequency
    3. Outlier ✓
    4. Class mark

26. 26. Find the arithmetic mean of: 12, 15, 18, 20, 25.

    1. 45%
    2. 60%
    3. 18 ✓
    4. 55%

27. 27. Find the arithmetic mean of: 4, 8, 12, 16, 20.

    1. 60%
    2. 45%
    3. 12 ✓
    4. 55%

28. 28. Find the arithmetic mean of: 10, 20, 30, 40.

    1. 25 ✓
    2. 45%
    3. 55%
    4. 60%

29. 29. Find the arithmetic mean of: 7, 9, 11, 13, 15.

    1. 60%
    2. 45%
    3. 11 ✓
    4. 55%

30. 30. Find the arithmetic mean of: 25, 30, 35, 40, 45.

    1. 45%
    2. 60%
    3. 55%
    4. 35 ✓

31. 31. Find the arithmetic mean of: 2, 4, 6, 8, 10.

    1. 60%
    2. 45%
    3. 55%
    4. 6 ✓

32. 32. Find the arithmetic mean of: 14, 16, 18, 20, 22.

    1. 60%
    2. 45%
    3. 55%
    4. 18 ✓

33. 33. Find the arithmetic mean of: 5, 10, 15, 20, 25, 30.

    1. 55%
    2. 60%
    3. 17.5 ✓
    4. 45%

34. 34. Find the arithmetic mean of: 6, 12, 18, 24.

    1. 45%
    2. 55%
    3. 15 ✓
    4. 60%

35. 35. Find the arithmetic mean of: 9, 12, 15, 18, 21.

    1. 55%
    2. 45%
    3. 15 ✓
    4. 60%

36. 36. Find the arithmetic mean of: 11, 13, 15, 17, 19.

    1. 60%
    2. 55%
    3. 15 ✓
    4. 45%

37. 37. Find the arithmetic mean of: 20, 25, 30, 35.

    1. 27.5 ✓
    2. 45%
    3. 60%
    4. 55%

38. 38. Find the median of the data: 3, 7, 9, 11, 15.

    1. 10
    2. 8
    3. 9 ✓
    4. 11

39. 39. Find the median of the data: 2, 4, 6, 8, 10.

    1. 8
    2. 5
    3. 6 ✓
    4. 7

40. 40. Find the median of the data: 5, 8, 12, 15, 20.

    1. 13
    2. 11
    3. 14
    4. 12 ✓

41. 41. Find the median of the data: 10, 20, 30, 40.

    1. 24
    2. 26
    3. 25 ✓
    4. 27

42. 42. Find the median of the data: 6, 9, 12, 15.

    1. 11.5
    2. 10.5 ✓
    3. 9.5
    4. 12.5

43. 43. Find the median of the data: 1, 3, 5, 7, 9, 11.

    1. 6 ✓
    2. 8
    3. 7
    4. 5

44. 44. Find the median of the data: 14, 16, 18, 20, 22, 24.

    1. 20
    2. 19 ✓
    3. 21
    4. 18

45. 45. Find the median of the data: 4, 6, 8, 10, 12.

    1. 10
    2. 7
    3. 8 ✓
    4. 9

46. 46. Find the median of the data: 11, 13, 15, 17.

    1. 14 ✓
    2. 16
    3. 13
    4. 15

47. 47. Find the median of the data: 2, 5, 7, 9, 12, 15, 18.

    1. 8
    2. 9 ✓
    3. 11
    4. 10

48. 48. Find the mode of: 2, 3, 3, 4, 5.

    1. 5
    2. 3 ✓
    3. 2
    4. 4

49. 49. Find the mode of: 7, 8, 8, 8, 9, 10.

    1. 9
    2. 7
    3. 10
    4. 8 ✓

50. 50. Find the mode of: 1, 2, 2, 3, 4.

    1. 3
    2. 4
    3. 1
    4. 2 ✓

51. 51. Find the mode of: 5, 5, 6, 7, 7, 7, 8.

    1. 8
    2. 7 ✓
    3. 6
    4. 5

52. 52. Find the mode of: 10, 12, 12, 13, 14.

    1. 14
    2. 12 ✓
    3. 13
    4. 10

53. 53. Find the mode of: 4, 4, 4, 6, 7, 8.

    1. 4 ✓
    2. 7
    3. 6
    4. 8

54. 54. Find the mode of: 9, 10, 10, 11, 12, 12, 12.

    1. 9
    2. 12 ✓
    3. 11
    4. 10

55. 55. Find the mode of: 1, 1, 2, 2, 2, 3.

    1. 1
    2. 2 ✓
    3. 5
    4. 3

56. 56. Find the range of: 12, 18, 25, 30, 42.

    1. 30 ✓
    2. 35
    3. 40
    4. 25

57. 57. Find the range of: 4, 9, 15, 22, 28.

    1. 34
    2. 19
    3. 24 ✓
    4. 29

58. 58. Find the range of: 100, 125, 150, 175.

    1. 85
    2. 70
    3. 80
    4. 75 ✓

59. 59. Find the range of: 7, 11, 19, 23, 30.

    1. 33
    2. 23 ✓
    3. 28
    4. 18

60. 60. Find the range of: 35, 40, 55, 60, 80.

    1. 45 ✓
    2. 50
    3. 40
    4. 55

61. 61. Find the range of: 2, 6, 9, 14, 20.

    1. 18 ✓
    2. 13
    3. 23
    4. 28

62. 62. Find the range of: 45, 50, 55, 70, 90.

    1. 50
    2. 40
    3. 55
    4. 45 ✓

63. 63. Find the range of: 11, 16, 21, 26, 31.

    1. 15
    2. 20 ✓
    3. 30
    4. 25

64. 64. Find the range of: 5, 15, 25, 35.

    1. 40
    2. 25
    3. 30 ✓
    4. 35

65. 65. Find the range of: 120, 135, 150, 180, 200.

    1. 75
    2. 85
    3. 80 ✓
    4. 90

66. 66. The frequencies of values 1, 2, 3 and 4 are 3, 5, 7 and 5 respectively. What is the total frequency?

    1. 18
    2. 20 ✓
    3. 15
    4. 22

67. 67. A class interval is 10–20. Its class mark is:

    1. 15 ✓
    2. 12
    3. 20
    4. 10

68. 68. Find the class mark of 30–40.

    1. 30
    2. 32
    3. 35 ✓
    4. 40

69. 69. Find the class mark of 45–55.

    1. 55
    2. 50 ✓
    3. 45
    4. 48

70. 70. If the class width is measured from 20 to 30, the width is:

    1. 10 ✓
    2. 15
    3. 20
    4. 5

71. 71. Frequencies are 4, 6, 8 and 12. What is the cumulative frequency up to the third class?

    1. 14
    2. 18 ✓
    3. 10
    4. 20

72. 72. Frequencies are 5, 7, 9 and 4. What is the total number of observations?

    1. 25 ✓
    2. 27
    3. 20
    4. 22

73. 73. If a value occurs 15 times in a total of 60 observations, its relative frequency is:

    1. 0.25 ✓
    2. 0.35
    3. 0.2
    4. 0.3

74. 74. A class has frequency 18 out of a total frequency of 90. Its relative frequency is:

    1. 0.15
    2. 0.2 ✓
    3. 0.25
    4. 0.3

75. 75. The cumulative frequencies are 5, 12, 20, 30. What is the frequency of the third class?

    1. 5
    2. 10
    3. 12
    4. 8 ✓

76. 76. The cumulative frequencies are 7, 15, 24, 40. Find the frequency of the fourth class.

    1. 9
    2. 18
    3. 16 ✓
    4. 15

77. 77. If frequencies are 10, 15, 20 and 25, what percentage belongs to the last class?

    1. 35.71 ✓
    2. 30
    3. 40
    4. 25

78. 78. In a frequency table, Σf = 50 and Σfx = 1,250. Find the mean.

    1. 20
    2. 22
    3. 30
    4. 25 ✓

79. 79. If Σf = 40 and Σfx = 960, the arithmetic mean is:

    1. 22
    2. 20
    3. 24 ✓
    4. 26

80. 80. A class interval 60–70 has class mark:

    1. 70
    2. 65 ✓
    3. 60
    4. 62

81. 81. The lower limit of the class 25–35 is:

    1. 20
    2. 30
    3. 25 ✓
    4. 35

82. 82. The upper limit of the class 25–35 is:

    1. 40
    2. 25
    3. 35 ✓
    4. 30

83. 83. A frequency polygon is obtained by joining points representing:

    1. class limits only
    2. percentages only
    3. cumulative frequencies only
    4. class marks and frequencies ✓

84. 84. An ogive is a graph of:

    1. simple frequency
    2. relative frequency only
    3. cumulative frequency ✓
    4. class width

85. 85. A bar chart is most suitable for:

    1. only ratios
    2. categorical or discrete data ✓
    3. continuous grouped data only
    4. only cumulative data

86. 86. The total of all relative frequencies is:

    1. 100
    2. 0.5
    3. 1 ✓
    4. 10

87. 87. If 30 out of 120 observations belong to a class, its percentage frequency is:

    1. 35
    2. 25 ✓
    3. 20
    4. 30

88. 88. A class frequency of 8 followed by 12 gives cumulative frequency:

    1. 22
    2. 18
    3. 12
    4. 20 ✓

89. 89. The frequency of a class can be found from successive cumulative frequencies by:

    1. averaging
    2. multiplication
    3. subtraction ✓
    4. division

90. 90. If the class limits are 10 and 20, the class mark is obtained by:

    1. 10 × 20
    2. (10 + 20) / 2 ✓
    3. 20 - 10
    4. 20 / 10

91. 91. A student scores 60, 70 and 80 in three tests with equal weights. Find the average.

    1. 70 ✓
    2. 65
    3. 75
    4. 72

92. 92. The mean of 5 numbers is 18. What is their total?

    1. 95
    2. 85
    3. 90 ✓
    4. 80

93. 93. The average of 8 observations is 25. Find their sum.

    1. 190
    2. 180
    3. 210
    4. 200 ✓

94. 94. The mean of 10 numbers is 15. If one more number 25 is added, what is the new mean?

    1. 17
    2. 18
    3. 16.5
    4. 15.91 ✓

95. 95. The mean of 6 numbers is 12. If one observation is removed, the remaining total is 50. Find the removed observation.

    1. 24
    2. 22 ✓
    3. 20
    4. 26

96. 96. The average age of 4 students is 16 years. A fifth student aged 20 joins them. Find the new average age.

    1. 16
    2. 18
    3. 16.8 ✓
    4. 17

97. 97. The mean of 7 values is 30. If their total increases by 14, what is the new mean?

    1. 31
    2. 32 ✓
    3. 33
    4. 30

98. 98. The average of 12 items is 40. If the total decreases by 24, the new average is:

    1. 36
    2. 42
    3. 38 ✓
    4. 39

99. 99. A worker earns Rs. 500 for 4 days and Rs. 700 for 2 days. Find the average daily earning.

    1. 575
    2. 566.67 ✓
    3. 550
    4. 600

100. 100. Find the weighted mean of 10 with weight 2 and 20 with weight 3.

     1. 17
     2. 15
     3. 14
     4. 16 ✓

101. 101. Find the weighted mean of 5 with frequency 4 and 10 with frequency 6.

     1. 8 ✓
     2. 8.5
     3. 7
     4. 7.5

102. 102. The mean of 4 numbers is 25. Three numbers are 20, 25 and 30. Find the fourth number.

     1. 20
     2. 35
     3. 30
     4. 25 ✓

103. 103. The mean of 5 observations is 14. Four observations are 10, 12, 15 and 18. Find the fifth.

     1. 15 ✓
     2. 14
     3. 16
     4. 13

104. 104. The average marks of 20 students is 60. What is the total marks?

     1. 1200 ✓
     2. 1000
     3. 1300
     4. 1100

105. 105. The mean of 9 observations is 22. Find their sum.

     1. 210
     2. 190
     3. 198 ✓
     4. 180

106. 106. A class of 10 students has average marks 70. If one student's marks are 80, what is the average of the remaining 9 students?

     1. 69.5
     2. 68.89 ✓
     3. 68
     4. 70

107. 107. The mean of 6 numbers is 25. If each number is increased by 5, the new mean is:

     1. 30 ✓
     2. 25
     3. 35
     4. 27

108. 108. If every observation in a data set is multiplied by 3, the mean is also:

     1. increased by 1
     2. multiplied by 3 ✓
     3. divided by 3
     4. unchanged

109. 109. If 10 is added to every observation, the mean:

     1. remains unchanged
     2. decreases by 10
     3. doubles
     4. increases by 10 ✓

110. 110. The average of 30 and 50 is:

     1. 45
     2. 40 ✓
     3. 50
     4. 35

111. 111. A group has 15 boys with mean age 18 and 10 girls with mean age 20. Find the combined mean age.

     1. 18
     2. 19
     3. 19.2
     4. 18.8 ✓

112. 112. The average of 6, 8, 10, 12 and x is 10. Find x.

     1. 14 ✓
     2. 15
     3. 16
     4. 12

113. 113. The mean of x, 12 and 18 is 15. Find x.

     1. 12
     2. 16
     3. 14
     4. 15 ✓

114. 114. Five values have mean 20. If one value 30 is replaced by 20, the new mean is:

     1. 19
     2. 16
     3. 20
     4. 18 ✓

115. 115. The mean of 4 values is 50. If each value is reduced by 10%, the new mean is:

     1. 50
     2. 40
     3. 45 ✓
     4. 48

116. 116. Which measure is most affected by extreme values?

     1. Median
     2. Mode
     3. Quartile
     4. Range ✓

117. 117. Which measure of central tendency is generally least affected by outliers?

     1. Median ✓
     2. Range
     3. Mean
     4. Variance

118. 118. Variance is based on:

     1. squared deviations from the mean ✓
     2. raw frequencies only
     3. median values only
     4. class marks only

119. 119. Standard deviation is the:

     1. square root of variance ✓
     2. range divided by mean
     3. square of variance
     4. mean of variance

120. 120. A smaller standard deviation generally indicates:

     1. lower frequency
     2. higher mean
     3. less dispersion ✓
     4. more dispersion

121. 121. Quartiles divide ordered data into:

     1. two equal parts
     2. four equal parts ✓
     3. ten equal parts
     4. three equal parts

122. 122. The second quartile Q2 is equal to the:

     1. Mean
     2. Median ✓
     3. Mode
     4. Range

123. 123. The first quartile Q1 represents approximately the:

     1. 10th percentile
     2. 50th percentile
     3. 25th percentile ✓
     4. 75th percentile

124. 124. The third quartile Q3 represents approximately the:

     1. 75th percentile ✓
     2. 25th percentile
     3. 90th percentile
     4. 50th percentile

125. 125. Percentiles divide data into:

     1. 4 equal parts
     2. 10 equal parts
     3. 100 equal parts ✓
     4. 50 equal parts

126. 126. The interquartile range is calculated as:

     1. Q1 + Q3
     2. Q3 − Q1 ✓
     3. Q3 / Q1
     4. Q2 − Q1

127. 127. If Q1 = 20 and Q3 = 50, the interquartile range is:

     1. 70
     2. 25
     3. 35
     4. 30 ✓

128. 128. If the smallest value is 10 and the largest is 90, the range is:

     1. 85
     2. 75
     3. 70
     4. 80 ✓

129. 129. Which graph is particularly useful for detecting skewness and outliers?

     1. Bar chart
     2. Box plot ✓
     3. Pie chart
     4. Pictogram

130. 130. A distribution with equal mean, median and mode is often:

     1. Bimodal
     2. Random
     3. Symmetrical ✓
     4. Always skewed

131. 131. A distribution with a long right tail is called:

     1. Symmetrical
     2. Negatively skewed
     3. Uniform
     4. Positively skewed ✓

132. 132. A distribution with a long left tail is called:

     1. Symmetrical
     2. Bimodal
     3. Positively skewed
     4. Negatively skewed ✓

133. 133. The coefficient of variation is useful for comparing:

     1. relative variability ✓
     2. only sample size
     3. only medians
     4. only frequencies

134. 134. Which is a measure of dispersion?

     1. Mode
     2. Standard deviation ✓
     3. Median
     4. Mean

135. 135. The square of standard deviation is:

     1. Variance ✓
     2. Mean deviation
     3. Coefficient of variation
     4. Range

136. 136. If variance is 49, standard deviation is:

     1. 7 ✓
     2. 5
     3. 6
     4. 8

137. 137. If standard deviation is 6, variance is:

     1. 30
     2. 12
     3. 42
     4. 36 ✓

138. 138. A data set with zero variance has:

     1. all observations equal ✓
     2. all observations different
     3. no median
     4. no mean

139. 139. The median divides ordered observations into:

     1. two halves ✓
     2. four groups
     3. three groups
     4. ten groups

140. 140. A bimodal distribution has:

     1. three modes
     2. two modes ✓
     3. one mode
     4. no mode

141. 141. The probability of an event that must occur is:

     1. 0.5
     2. 0
     3. 1 ✓
     4. 2

142. 142. The probability of an impossible event is:

     1. 0 ✓
     2. -1
     3. 0.5
     4. 1

143. 143. When a fair coin is tossed once, the probability of heads is:

     1. 0.25
     2. 0.5 ✓
     3. 0.75
     4. 1

144. 144. A fair die is rolled. The probability of getting a 6 is:

     1. 0.25
     2. 0.5
     3. 0.16666666666666666 ✓
     4. 0.3333333333333333

145. 145. A fair die is rolled. The probability of an even number is:

     1. 0.5 ✓
     2. 0.25
     3. 0.3333333333333333
     4. 0.6666666666666666

146. 146. From numbers 1 to 10, the probability of selecting an odd number is:

     1. 0.5 ✓
     2. 0.7
     3. 0.6
     4. 0.4

147. 147. A bag contains 3 red and 2 blue balls. The probability of drawing a red ball is:

     1. 0.8
     2. 0.6 ✓
     3. 0.4
     4. 0.5

148. 148. A bag contains 4 green and 6 yellow balls. The probability of yellow is:

     1. 0.4
     2. 0.7
     3. 0.5
     4. 0.6 ✓

149. 149. The probability of any event lies between:

     1. −1 and 1
     2. 1 and 10
     3. 0 and 1 ✓
     4. 0 and 100

150. 150. Two events that cannot occur together are called:

     1. Complementary only
     2. Dependent
     3. Mutually exclusive ✓
     4. Independent

151. 151. If P(A) = 0.35, then P(not A) is:

     1. 0.65 ✓
     2. 0.35
     3. 0.5
     4. 0.75

152. 152. The sum of probabilities of all outcomes in a sample space is:

     1. 1 ✓
     2. 0.5
     3. 100
     4. 0

153. 153. Correlation measures the:

     1. strength and direction of association ✓
     2. range only
     3. average only
     4. frequency only

154. 154. A correlation coefficient close to +1 indicates:

     1. perfect randomness
     2. strong negative relationship
     3. no relationship
     4. strong positive relationship ✓

155. 155. A correlation coefficient close to −1 indicates:

     1. strong negative relationship ✓
     2. zero variance
     3. no relationship
     4. strong positive relationship

156. 156. A correlation coefficient of 0 generally indicates:

     1. perfect positive relationship
     2. no linear relationship ✓
     3. maximum variance
     4. perfect negative relationship

157. 157. A scatter plot is commonly used to display:

     1. only percentages
     2. relationship between two quantitative variables ✓
     3. one categorical variable only
     4. only frequencies

158. 158. The variable believed to explain another variable is often called:

     1. Parameter
     2. Frequency
     3. Dependent variable
     4. Independent variable ✓

159. 159. The response variable is commonly called the:

     1. Dependent variable ✓
     2. Class variable
     3. Constant
     4. Independent variable

160. 160. A positive correlation means that variables tend to:

     1. move in the same direction ✓
     2. be identical
     3. move in opposite directions
     4. have no change

161. 161. A negative correlation means variables tend to:

     1. move in opposite directions ✓
     2. move together
     3. have no variance
     4. be equal

162. 162. Correlation does not necessarily imply:

     1. Causation ✓
     2. measurement
     3. data
     4. association

163. 163. A sample statistic is used to estimate a population:

     1. Parameter ✓
     2. Frequency
     3. Class interval
     4. Graph

164. 164. The symbol commonly used for population mean is:

     1. x̄
     2. s
     3. μ ✓
     4. r

165. 165. The symbol commonly used for sample mean is:

     1. σ
     2. x̄ ✓
     3. ρ
     4. μ

166. 166. Marks of five students are 55, 60, 65, 70 and 75. Find the mean.

     1. 70
     2. 62
     3. 65 ✓
     4. 60

167. 167. The temperatures recorded over four days are 20°C, 22°C, 24°C and 26°C. Find the mean temperature.

     1. 23 ✓
     2. 22
     3. 24
     4. 25

168. 168. Find the median of 12, 5, 18, 9 and 15.

     1. 12 ✓
     2. 9
     3. 15
     4. 11

169. 169. The data are 4, 6, 6, 8, 10, 10, 10, 12. Find the mode.

     1. 8
     2. 6
     3. 12
     4. 10 ✓

170. 170. Find the range of marks 45, 60, 72, 88 and 95.

     1. 48
     2. 45
     3. 50 ✓
     4. 55

171. 171. A class has frequencies 5, 8, 12 and 15. What is the total number of students?

     1. 35
     2. 40 ✓
     3. 38
     4. 42

172. 172. The mean of 20 observations is 35. If their total is divided equally among them, each gets:

     1. 30
     2. 35 ✓
     3. 40
     4. 32

173. 173. The average score of 6 players is 42. What is their combined score?

     1. 250
     2. 252 ✓
     3. 240
     4. 260

174. 174. A data set has values 2, 4, 6, 8 and 10. What happens to the mean if 2 is replaced by 12?

     1. It remains unchanged
     2. It increases by 10
     3. It decreases by 2
     4. It increases by 2 ✓

175. 175. For the data 10, 20, 30, 40 and 50, which measure equals 30?

     1. Mean only
     2. Median only
     3. Mean, median and mode cannot all equal 30 ✓
     4. Mean and median

176. 176. The mean of 3, 6, 9 and 12 is:

     1. 7
     2. 8
     3. 7.5 ✓
     4. 6

177. 177. The median of 2, 4, 6, 8, 10 and 12 is:

     1. 6
     2. 7.5
     3. 8
     4. 7 ✓

178. 178. If a data set contains 7 observations, the median is the:

     1. 4th observation after ordering ✓
     2. 7th observation
     3. 3rd observation
     4. 5th observation

179. 179. If a data set contains 8 observations, the median is the average of the:

     1. 5th and 6th observations
     2. 1st and 8th observations
     3. 3rd and 4th observations
     4. 4th and 5th observations ✓

180. 180. A score of 90 occurs 4 times in a class of 20 students. Its relative frequency is:

     1. 0.15
     2. 0.2 ✓
     3. 0.25
     4. 0.1

181. 181. Out of 200 respondents, 50 prefer option A. What percentage prefer A?

     1. 35
     2. 20
     3. 25 ✓
     4. 30

182. 182. If 40% of 150 students are female, how many females are there?

     1. 55
     2. 50
     3. 60 ✓
     4. 65

183. 183. A survey records 24 successes out of 80 trials. The relative frequency of success is:

     1. 0.4
     2. 0.25
     3. 0.3 ✓
     4. 0.35

184. 184. A distribution has mean 50 and standard deviation 5. Which value is one standard deviation above the mean?

     1. 55 ✓
     2. 50
     3. 45
     4. 60

185. 185. For mean 100 and standard deviation 15, one standard deviation below the mean is:

     1. 80
     2. 115
     3. 85 ✓
     4. 90

186. 186. If all observations are increased by 4, the standard deviation:

     1. remains unchanged ✓
     2. doubles
     3. increases by 4
     4. decreases by 4

187. 187. If all observations are multiplied by 2, the standard deviation:

     1. increases by 4 only
     2. is multiplied by 2 ✓
     3. is divided by 2
     4. remains unchanged

188. 188. The mean is most appropriate for data that are:

     1. purely nominal only
     2. only alphabetical
     3. numerical and not heavily distorted by extreme values ✓
     4. always categorical

189. 189. The mode is particularly useful for finding the:

     1. total frequency only
     2. most common category ✓
     3. middle observation only
     4. range

190. 190. The median is especially useful when data contain:

     1. zero frequencies
     2. extreme values ✓
     3. only categories
     4. no observations

191. 191. A frequency distribution with class intervals 0–10, 10–20, 20–30 has how many classes?

     1. 3 ✓
     2. 5
     3. 4
     4. 2

192. 192. The midpoint of the class interval 70–80 is:

     1. 70
     2. 75 ✓
     3. 72
     4. 80

193. 193. If cumulative frequency before a class is 25 and after including the class is 40, the class frequency is:

     1. 10
     2. 12
     3. 15 ✓
     4. 20

194. 194. A pie chart sector represents 90° of a circle. What percentage of the total does it represent?

     1. 25 ✓
     2. 50
     3. 20
     4. 30

195. 195. A sector of 180° in a pie chart represents:

     1. 25
     2. 60
     3. 50 ✓
     4. 40

196. 196. If 25% of observations fall in a category and total observations are 240, the category frequency is:

     1. 50
     2. 65
     3. 60 ✓
     4. 55

197. 197. The ratio of frequency 15 to total frequency 60 is:

     1. 0.3
     2. 0.35
     3. 0.2
     4. 0.25 ✓

198. 198. The median of 1, 3, 5, 7, 9 is:

     1. 5 ✓
     2. 4
     3. 6
     4. 3

199. 199. The mean of 100, 200 and 300 is:

     1. 250
     2. 180
     3. 150
     4. 200 ✓

200. 200. A data set has no repeated values. Its mode is:

     1. The median
     2. The mean
     3. No mode ✓
     4. The range