CBSE Data Science Class 9 Solution – Data Visualizations
CBSE Data Science Class 9 Solution Student Handbook Chapter 3 Data Visualizations all Questions and Answers Solution by Data Science Teacher. Net Ex. Here provided all Data Science Solution for Class 9. This Exercise includes Objective Type Questions, Standard Questions, Higher Order Thinking Skills (HOTS), Applied Project.
Objective Type Questions
1) Data can be visualized using :
a) Graphs
b) Maps
c) Charts
d) All of the above
Ans. d
2) Which of the following statements is false?
a) Data visualizations can absorb information quickly.
b) Data visualization decreases the insights and takes slower decisions
c) Data visualization is a type of visual art.
d) None of the above
Ans. B
3) Which of the following is a use of data visualization ?
a) Healthcare
b) Sales and Marketing
c) Politics/Campaigning
d) All of the above
ans. D
4) Bar Graph is a
a) One-dimensional graph
b) Two-dimensional graph
c) Graph with no dimension
d) None of the above
Ans. a
5) The data represented through a histogram can help in finding graphically the
a) Median
b) Mean
c) Mode
d) All of the above
Ans. C
6) Pie chart is a
a) One-dimensional graph
b) Two-dimensional graph
c) Graph with no dimension
d) None of the above
Ans. B
7) Can a Line chart be used to plot multiple variables.
a) Yes
b) No
Ans. a
8) The height of your classmates is recorded and arranged in ascending order. The data is represented as histogram. What type of shape does the histogram have
a) Right-skewed Distribution
b) Left-skewed Distribution
c) Bimodal Distribution
d) Random Distribution
Ans. B
Standard Questions
1) Give a examples of real-life use of data visualization.
Ans :- Below are the few examples of real-life use of data visualization which are :-
a) Tracking students progress with score cards :- Generally every educational institution records the score cards of every students for a longer period of time. The maintaining / recording of students scorecard helps the parents and teachers in analysing the students progress. It also helps in understanding the students strengths and weakness in a particular subject.
As a result the teacher and parent can make proper assessment/ help/guidance to the students.
b) Identifying usage trend of a website :- Assume that you are the website administrator and you are keen interested in knowing/identifying the pattern whenever many of the people visits the website. for doing this it is essential for you to track the visitors/users who visits the websites and the track of the time when the visitors had visited etc. if the same kind of data is been placed/plotted on the graph, then definitely you’ll quickly identify about the time when the users or visits mostly visits.
c) Monitoring the goals and results of a sales executives :- Every business organizations set up their business goals and as per it the sales executives works on it in order of achieving it. After visualizing the sales records in the charts or graphs pictures, the sales executives can have a clear idea about how much nearer to their desired goal and what else steps they are needed to take.
d) Visualizing spread and inputs of pandemics :- As we are much aware that recently the entre world is been effected by the one of the greatest pandemic COVID 19. Data Visualizations techniques enables the government and other bodies in identifying the mostly affected countries or regions/areas etc. As a result, it also helps the government or other bodies in taking preventing measures/ actions.
2) Explain the importance of data visualizations.
Ans :- Data visualizations is a method/tool of showing/displaying the raw data in the way of different graphs which later helps the users in exploring of data and uncovering the actual idea. There is a presence of different types of information all around us, so it is a very challenging task for the user in viewing the data and getting the actual idea of it. If the data is displayed in the form of various graph charts, maps etc, which will provide the user the context of the data. Even it will be very helpful in converting the complicated/simple data into the simple way. This will help the human mind in understanding the importance of the data. Visualizations helps us in recognizing and choosing the right form of data from different types of meaningless data trends, patterns, and outliers. With the help of Data visualization technique, it has become much easier in communicating the information in a faster way. Such technique benefits the viewers, business analyst and the company executives in analysing the areas where the changes are required to be made, considering/ identifying the factors which determines the customers satisfaction and dis satisfaction. Data visualization also enables the customers, company owners, decision makers etc in predicting about the total revenue and the potential growth.
3) Explain a few graphs/charts used for data visualizations.
Ans :- The graphs/charts which are used for data visualizations are as followed :-
a) Dot Plots :- It is the graphical method of showing of data in the form of dots. Dot Plots were earlier used before the invention of computers in the year 1884 where the data was been distributed hand drawn. It was used to display the quantitative values which were associated with the categorical values.
b) Bar Graphs :- It the graphical method of data representation where different heights of bars are been used. As the data is been represented with the help of bars in Bar Graph, so the plotting of the data could be easily done in the horizontally and vertically manner. The another name of vertical bar graph was charts or graphs. In the bar graph, the data (elements) are represented in such a manner that the bars do not touches each other.
c) Histogram :- It is the representation or plotting of data or frequencies against the intervals. It is necessary to convert the data into intervals in order to draw histogram. Such types of intervals are also called as logical ranges or bins. Histogram also makes use of different heighted bars for representing of data. We can summarise the discrete and continuous data with the help of histogram. Histogram also shows the number of data points that falls within a given set of values (called bins) to provide a visual representation of numeric data. Similar to vertical bar graph, histogram does not show the gaps between the bars. Histogram also enables in representing the value of the frequency distribution mode graphically.
4) Give few examples of Multi-variable and Single – variable plots
Ans :- The examples of Multi-variable and Single-variable plots are as followed :-
a) Single-variable plots :- In the following example we can notice, we have a survey of 35 students on what food they prefer. Below is the response in the form of data :-
Food Item | No of Students |
Dosa | 10 |
Vada Pav | 25 |
Pizza | 20 |
Ice Cream | 30 |
b) Multi-variable plots :- Following we have the survey of how many students enrolled in schools 1 and 2 from 1995-2006. The data is been given below :-
b) Multi-variable plots :- Following we have the survey of how many students enrolled in schools 1 and 2 from 1995-2006. The data is been given below :-
Year |
No of Students in School 1 | No of students in school 2 |
2011 | 114 |
129 |
2012 |
127 | 122 |
2013 | 131 |
151 |
2014 |
130 | 118 |
2015 | 125 |
123 |
2016 |
116 | 130 |
2017 | 119 |
122 |
2018 |
140 | 138 |
2019 | 146 |
133 |
2020 |
137 | 145 |
2021 | 122 |
130 |
2022 |
141 |
110 |
5) The value of pi (n) up to 55 decimal places is given below :
3.1415926535 8979323846 2643383279 5028841971 6939937510 58209
a) Make a frequency distribution table for the digits from 0 to 9 after the decimal point
Digits |
Frequency |
0 |
3 |
1 |
5 |
2 |
6 |
3 |
8 |
4 |
4 |
5 |
6 |
6 |
4 |
7 |
4 |
8 |
6 |
9 |
9 |
Total |
55 |
c) Find the most and the least frequently occurring digits?
Least Frequently Occurring digits |
Most Occurring Digits |
0 —> 2 Times |
9 —> 9 Times |
Higher Order Thinking Skills (HOTS)
1) Record the number of students absent in your class in the past one month in a tabular format. Display the data as a data plot. Find the Maximum and the mean of the data.
2) The height of your classmates varies from student to student. Record the height of your classmates in a tabular format. Visualize the data using a histogram and find the mode of the height of your class.
3) Form statistical investigative questions to find the favourite, fruit of your class. Collect the data, analyze the data and then interpret the results for your school’s favourite fruit.
Applied Project
Over the past few decades, the earth’s temperature has been rising. Collect the data from various sources, analyze the data, represent the data using various plots.