MATH 215 Introduction to Statistics
Assignment 1
Athabasca University
, (Revision 10)
Assignment / 1
This assignment covers content from Unit 1 of the course. It assesses your knowledge of many of the
statistical terms that will be used throughout the course, as well as your ability to organize, display and
summarize data.
Instructions
• Show all your work and justify all of your answers and conclusions, except for the TRUE/FALSE
questions.
• Keep your work to 4 decimals, unless otherwise stated.
(22 total marks)
1. Observations from the first 25 days of the year showed that the following number of pedestrians
used a particular crosswalk on each day:
19 132 25 78 62 101 84 32 99 71 43 56 64 81 59 67 43 97 105 91 31 66 76 87 125
(8 marks)
Construct a frequency distribution for this data using a lower limit for the first class of 15 and a
class width of 20. Indicate the class limits, boundaries, midpoints, frequencies and cumulative
frequencies.
Number of Class Class Frequency Relative Cumulative
pedestrians Boundaries midpoints frequency frequency
15 - 34 14.5 - 34.5 24.5 4 4/25 = 0.16 4
35 - 54 34.5 - 54.5 44.5 2 2/25 = 0.08 4+2 = 6
55 - 74 54.5 - 74.5 64.5 7 7/25 = 0.28 4+2+7 = 13
75 - 94 74.5 - 94.5 84.5 6 6/25 = 0.24 4+2+7+6 =19
95 - 114 94.5 - 114.5 104.5 4 4/25 = 0.16 4+2+7+6+4=23
115 - 134 114.5 - 134.5 124.5 2 2/25 = 0.08 4+2+7+6+4+2 = 25
Class midpoint = (upper limit + lower limit) / 2
troduction to Statistics Assignment 1
Assignment 1
Athabasca University
, (Revision 10)
Assignment / 1
This assignment covers content from Unit 1 of the course. It assesses your knowledge of many of the
statistical terms that will be used throughout the course, as well as your ability to organize, display and
summarize data.
Instructions
• Show all your work and justify all of your answers and conclusions, except for the TRUE/FALSE
questions.
• Keep your work to 4 decimals, unless otherwise stated.
(22 total marks)
1. Observations from the first 25 days of the year showed that the following number of pedestrians
used a particular crosswalk on each day:
19 132 25 78 62 101 84 32 99 71 43 56 64 81 59 67 43 97 105 91 31 66 76 87 125
(8 marks)
Construct a frequency distribution for this data using a lower limit for the first class of 15 and a
class width of 20. Indicate the class limits, boundaries, midpoints, frequencies and cumulative
frequencies.
Number of Class Class Frequency Relative Cumulative
pedestrians Boundaries midpoints frequency frequency
15 - 34 14.5 - 34.5 24.5 4 4/25 = 0.16 4
35 - 54 34.5 - 54.5 44.5 2 2/25 = 0.08 4+2 = 6
55 - 74 54.5 - 74.5 64.5 7 7/25 = 0.28 4+2+7 = 13
75 - 94 74.5 - 94.5 84.5 6 6/25 = 0.24 4+2+7+6 =19
95 - 114 94.5 - 114.5 104.5 4 4/25 = 0.16 4+2+7+6+4=23
115 - 134 114.5 - 134.5 124.5 2 2/25 = 0.08 4+2+7+6+4+2 = 25
Class midpoint = (upper limit + lower limit) / 2
troduction to Statistics Assignment 1
