NCERT Solutions Class 8 Maths Chapter 4 Data Handling Exercise 4.2

The NCERT Solutions Class 8 Maths Chapter 4 Exercise 4.2 helps you to learn to represent data in a circle graph also called a pie chart. This exercise also teaches you to divide data into parts and represent them in a circle shape that clearly represents information. This topic is useful for your CBSE exam, project work, and competitive exams such as Olympiads. It will also help your ability to work with data in the real world.

The questions follow the latest NCERT syllabus and are explained stepwise in a simple manner. These NCERT Solutions are also a good way to revise the chapter and prepare for your school tests.

1.0Download NCERT Solutions Class 8 Maths Chapter 4 Data Handling Exercise 4.2: Free PDF

These NCERT Solutions for Class 8 Maths Chapter 4 Exercise Exercise 4.2 focuses on representing data in pie charts. The explanations are provided step-by-step making the learning easy. Download for free PDF for practice and revision from below:

2.0Key Concepts in Exercise 4.2 of Class 8 Maths Chapter 4

Key concepts covered in exercise 4.2 of Class 8 Maths Chapter 4 include:

• Understanding circle graphs or pie charts
• Converting data into percentages
• Drawing pie charts based on data
• Interpreting pie charts and comparing data visually

3.0NCERT Class 8 Maths Chapter 4: Other Exercises

4.0NCERT Class 8 Maths Chapter 4 Exercise 4.2: Detailed Solutions

• A survey was made to find the type of music that a certain group of young people likes in a city. Following pie chart shows the findings of this survey. From this pie chart answer the following questions:
  
  (i) If 20 people like classical music, how many young people were surveyed? (ii) Which type of music is liked by the maximum number of people? (iii) If a cassette company were to make 1000 CD's, how many of each type would it make? Sol. (i) Let x be the number of young people surveyed. $\therefore 10\%$ of $\mathrm{x}=20$ $\Rightarrow \frac{10}{100}\times \mathrm{x}=20\Rightarrow \mathrm{x}=20\times 10=200$ Thus, number of young people surveyed $=$ 200 (ii) Light music is liked by the maximum number of people. (iii) Number of CD's in respect of Classical music $=\frac{10}{100}\times 1000=100$ Semi-classical music $=\frac{20}{100}\times 1000=200$ Folk music $=\frac{30}{100}\times 1000=300$ Light music $=\frac{40}{100}\times 1000=400$
• A group of 360 people were asked to vote for their favourite season from the three seasons-Rainy, winter and summer.
  
  (i) Which season got the most votes? (ii) Find the central angle of each sector. (iii) Draw a pie chart to show this information. Sol. (i) The winter season got the maximum votes. (ii) The proportion of sectors (winter, summer and rainy seasons) are as $\frac{150}{360}=\frac{5}{12},\frac{90}{360}=\frac{1}{4}$, and $\frac{120}{360}=\frac{1}{3}$ respectively. (iii) Central angle for winter season $={\left(\frac{150}{360}\times 360\right)}^0=150^{\circ }$ Central angle for summer season $={\left(\frac{90}{360}\times 360\right)}^{\circ }=90^{\circ }$ and central angle for rainy season $={\left(\frac{120}{360}\times 360\right)}^{\circ }=120^{\circ }$ Now, the various components may be shown by the adjoining pie chart.
  
• Draw a pie chart showing the following information. The table shows the colours preferred by a group of people.

Sol.

• The adjoining pie chart gives the marks scored in an examination by a student in Hindi, English, Mathematics, Social Science and Science. If the total marks obtained by the students were 540, answer the following questions. (i) In which subject did the student score 105 marks? (Hint: for 540 marks, the central angle $=$ $360^{\circ }$. So, for 105 marks, what is the central angle?
  
  (ii) How many more marks were obtained by the student in Mathematics than in Hindi? (iii) Examine whether the sum of the marks obtained in Social Science and Mathematics is more than that in Science and Hindi. (Hint : Just study the central angles.) Sol. (i) For 540 marks, the central angle $=$ $360^{\circ }$ $\therefore$ For 1 mark, the central angle $={\left(\frac{360}{540}\right)}^0={\left(\frac{2}{3}\right)}^0$ $\therefore$ For 105 marks, the central angle $={\left(\frac{2}{3}\times 105\right)}^0=70^{\circ }$ Hence, from the given pie chart, the subject is Hindi. (ii) Difference between the central angles made by the subject of Mathematics and Hindi $=90^{\circ }-70^{\circ }=20^{\circ }$. For the central angle of $360^{\circ }$, marks obtained $=540$ For the central angle of $1^{\circ }$, marks obtained $=\frac{540}{360}=\frac{3}{2}$ For the central angle of $20^{\circ }$, marks obtained $=\frac{3}{2}\times 20=30$ Marks Hence, 30 more marks were obtained by the student in Mathematics than Hindi. (iii) Sum of the central angles made by Social Science and Mathematics $=65^{\circ }+90^{\circ }=$ $155^{\circ }$. and the sum of the central angles made by Science and Hindi $=80^{\circ }+70^{\circ }=150^{\circ }$. Since, Science $155^{\circ }>150^{\circ }$, therefore, the sum of the marks obtained in Social Science and Mathematics is more than that in Science and Hindi.
• The number of students in a hostel, speaking different languages is given below. Display the data in a pie chart.

Sol.

5.0Key Features and Benefits of Class 8 Maths Chapter 4 Exercise 4.2

• The Solutions are based on the latest NCERT syllabus and are helpful in preparing for CBSE exam.
• These provide clear steps to convert data into various percentages and pie charts.
• The Solutions also explains very complex ideas visually in simple and relatable examples.
• Helps students to prepare for Olympiad questions involving visual representation of data.
• Regular practice will improve confidence in charts and visual data understanding.
• Enhances data interpretation skills and analytical thinking to inform real-life problems.