MTH3003
SESSION 2021/2022 SEM 1
TUTORIAL 1
1. Identify the following quantitative variables as discrete or continuous:
a) Population in a particular area of the Selangor.
b) Weight of newspapers recovered for recycling on a single day.
c) Time to complete a statistics exam.
d) Number of consumers in a poll 0f 1000 who consider nutritional
labeling on food products to be important.
2. Fifty people are grouped into four categories (A, B, C, D) and the
number of people who fall into each category is shown in the table:
Category Frequency
A
11
B
14
C
20
D
5
a) What is the experimental unit?
b) What is the variable being measured? It is qualitative or
quantitative?
c) Construct a pie chart to describe the data.
d) Construct a bar chart to describe the data.
e) Does the shape of the bar chart in part d change depending on the
order of presentation of the four categories? Is the order of
presentation important?
f) What proportion of the people are in category B, C or D?
g) What percentage of the people are not in category B?
3. Construct a stem and leaf plot for these 50 measurements:
3.1
2.9
3.8
2.5
4.3
4.9
2.1
6.2
3.6
5.7
2.8
3.5
2.5
5.1
3.7
3.6
4.0
2.9
4.8
4.6
2.5
3.7
2.8
1.6
4.0
4.5
2.7
5.1
3.6
5.6
3.5
4.0
1.8
6.1
4.9
3.7
4.4
5.6
4.7
4.2
4.1
3.7
2.2
3.9
3.1
4.9
4.2
3.4
3.9
3.9
a) Describe the shape of the data distribution. Do you see any
outliers?
b) Use the stem and leaf plot to find the smallest observation.
c) Find the eighth and ninth largest observations.
4. Answer questions 1 – 5 based on the following data which gives the
distance traveled (in thousand km) by 100 salesmen from a particular
organization.
40
43
49
55
65
73
30
36
32
10
26
29
31
44
54
60
31
50
27
65
41
93
35
18
97
41
32
31
75
52
40
46
36
33
67
40
34
56
30
20
39
32
84
38
88
29
48
35
68
36
34
44
81
28
44
24
76
15
24
38
61
71
51
42
39
58
38
26
37
38
42
45
51
11
42
47
52
28
30
43
47
62
52
48
35
53
63
41
20
21
23
36
66
55
50
45
41
45
50
55
a) Find the range. Construct a frequency, relative frequency and
cumulative relative frequency table (HINT: number of classes = 9,
lower class boundary of the first class = 10).
b) Construct a histogram, a frequency polygon and an ogive. Using
the ogive, estimate the number of salesman whose travelling
distance is less than 44 thousand km.
c) Find the mode, median and variance for the group data.
d) Find P20 and P85 for the group data and interpret your answer.
e) Construct a stem and leaf plot and interpret it.
Answer questions 5 – 7 based on the following data.
0
5.
4
2
4
5
8
9
8
6
a) Calculate the mean, mode and median.
b) Calculate the variance and standard deviation.
c) Calculate the coefficient of variation.
6. Find P40 and interpret your answer.
7. Construct a box plot and give your interpretation.
**Questions marked red must be sent to the demonstrator**
4