STA201 Assignment 1 

STA201 Assignment 1 
Question 1
The following table shows some information on a variety of different vehicles. Using the
information given in table 1, answer question 1(A) – 1(C).
Table-1: Cars
Model Number
of gears
Size of
Engine
Transmission Vehicle
Class
Highway
Mileage
City
Mileage
Model
Year
Allion 6 3.4 Manual Midsize
Car
22 17 1997
Axio 7 2.5 Manual Small Car 26 22 2000
Aqua
Hybrid
8 3.5 Automatic Small Car 30 24 2021
Corolla 5 3 Manual Midsize
Car
25 22 2001
Vezel 8 6.8 Automatic Large Car 18 15 2022
Premio 6 3.3 Automatic Midsize
Car
22 17 2016
Harrier 7 4.2 Automatic Large Car 18 15 2020
Naoh 7 5.4 Automatic Large Car 20 16 2018
Question 1(A)
(i) How many variables are listed in table 1?
(ii) Classify the variables according to their types (Qualitative / Quantitative).
(iii) Construct a frequency distribution table to represent the summary information of the
variable “Vehicle Class” and display the results in a pie chart.
Question 1(B)
Complete the following table and answer the questions:
Table 2: Frequency Distribution of Transmission by Number of Gears
Transmission
Number of Gears
Total
5 6 7 8
Automatic
Manual
Total
(i) What is the modal response for the variable “Transmission”? (Which has the highest
frequency?)
(ii) What proportion of vehicles have seven gears?
(iii) What proportion of Automatic vehicles have eight gears?
(iv) What proportion of vehicles with six gears are Manual?
(v) Construct a side-by-side bar chart to represent the information given in table 2.
Question 1(C)
Complete the following table and answer the questions:
Table 3: Frequency distribution of Highway Mileage
Highway
Mileage Tally Frequency Relative frequency Cumulative relative
frequency
15 – 20
20 – 25
25 – 30
30 – 35
(i) What proportion of vehicles have mileage between 20 and 30 Highway Mileage?
(ii) What proportion of vehicles have mileage of at least 30 Highway Mileage?
(iii) Construct a histogram to display the data represented in table 3.
Question 2
Recall that 65 purchasers have participated in a survey and have rated the XYZ-Box video game
system. The composite ratings that have been obtained are as follows:
 39 38 40 40 40 46 43 38 44 44 44
 45 42 42 47 46 45 41 43 46 44 42
 38 46 45 44 41 45 40 36 48 44 47
 42 44 44 43 43 46 43 44 44 46 43
 42 40 42 45 39 43 44 44 41 39 45
 41 39 46 45 43 47 41 45 45 41
(a) Construct a stem-and-leaf display for the 65 composite ratings.
(b) If we consider a purchaser to be “very satisfied” if his or her composite score is at least
42, can we say that almost all purchasers of the XYZ-Box video game system are “very
satisfied”. Describe in your own words.
Question 3
A group of colleagues is going to Safari Park for a day. They arranged their trip into three halves
and planned to travel at a speed of 68 kilometers per hour on their journey to their goal. Their top
speeds were 72 km/h and 88 km/h for the first and second parts, respectively. If they are to meet
their intended average speed, what speed should they maintain throughout the third part of their
journey?
Question 4
Suppose, you spent Tk. 3,500,000 to buy a new car. After the first year, the car depreciates by
40%, 20% after the second year, and 10% after the third year.
(a) What is the average rate of depreciation per year after three years?
(b) What will be the value of the car after three years of use?
Question 5
Blood cocaine concentration (mg/L) was determined both for a sample of individuals who had
died from cocaine-induced excited delirium (ED) and for a sample of those who had died from a
cocaine overdose without excited delirium; survival time for people in both groups was at most 6
hours.
ED:
0 0 0 0 0.1 0.1 0.1 0.1 0.2 0.2
0.3 0.3 0.3 0.3 0.4 0.4 0.5 0.5 0.5 0.5
0.6 0.7 0.7 0.8 0.9 1 1.5 2 2.1 2.5
3 3.9 5 8.5 11 12.5 14
NON-ED:
0 0 0 0.1 0.1 0.2 0.3 0.3 0.3 0.5
0.6 0.6 0.8 0.8 0.8 0.8 1 1.5 2 2.2
2.6 3.3 5 5.5 7 7.7 9 11 12 15
18 19.5 22 24 25.5 25.5 25.5 27 27.5 28
(a) Determine the three-quartile values for blood cocaine concentration for both ED and
Non-ED samples.
(b) Construct a comparative boxplot (two boxplots on the same set of axes, one above the
other)
(c) Describe (Compare and Contrast) the ED and Non-ED samples in your own words from
the boxplot.