CBSE Class 9 Mathematics Chapter 14 Statistics NCERT Solutions

Reviewed by · Updated on

NCERT Solutions PDF Class 9 PDF

CBSE Class 9 Mathematics Chapter 14 delves into the foundational concepts of Statistics. This chapter introduces students to the world of data, explaining how to differentiate between primary and secondary data and the importance of organizing information. You'll learn to use frequency distribution tables to structure data effectively. The solutions provide clear, step-by-step guidance on collecting, classifying, and representing data, ensuring a solid understanding of these essential statistical tools. This resource is designed to build a strong foundation, helping you grasp key concepts and prepare thoroughly for your examinations with accurate and easy-to-understand explanations.

Home

Quick info

BoardCBSE
ClassClass 9
SubjectMathematics
Session2026
LanguageEnglish
TypeNCERT Solutions
ChapterChapter 14

Chapter summary

Chapter 14 on Statistics for CBSE Class 9 Maths focuses on the basics of data handling. The NCERT Solutions cover the initial steps of data collection, distinguishing between primary and secondary data sources. It also emphasizes the creation of frequency distribution tables to organize raw data, making it easier to interpret. These solutions aim to equip students with the foundational skills needed to understand statistical information presented in various forms.

Learning outcomes

  • Understand the concept of data in statistics.
  • Differentiate between primary and secondary data.
  • Collect examples of data from daily life.
  • Classify collected data as primary or secondary.
  • Construct a frequency distribution table for a given set of data.
  • Identify the most common and rarest data points from a frequency table.

Topics covered

Paper topics

  • Data
  • Data Collection
  • Primary Data
  • Secondary Data
  • Classification of Data
  • Frequency Distribution Table
  • Tally Marks
  • Most Common Data
  • Rarest Data
  • Statistics Basics

Important topics

  • Primary vs. Secondary Data
  • Constructing Frequency Distribution Tables
  • Identifying Most Common and Rarest Data
  • Data Collection Examples

PDF preview

Read page by page below. PDF is streamed from the official NCERT website — no download button on this page.

Loading document …
Page of
Loading page …

Questions and Solutions

Question 1

Give five examples of data that you can collect from your day-to-day life.
Solution:

We can collect various types of data from our daily lives. Here are five examples:

  1. The number of females per 1000 males in different states of India.
  2. The weights of all the students in our classroom.
  3. The annual production of wheat in our country over the past 10 years.
  4. The total number of plants present in our local area or neighborhood.
  5. The amount of rainfall recorded in our city during the last 10 years.

Question 2

Classify the data in Question 1 above as primary or secondary data.
Solution:

Data can be classified based on its source:

  • Primary Data: This is the information collected directly by the investigator for a specific purpose. It is original data gathered firsthand.
  • Secondary Data: This is information that has already been collected by someone else and is available from various sources. It is gathered from existing records or publications.

Applying this to the examples in Question 1:

  • 1. Number of females per 1000 males in various states: This data is usually available from government census reports or statistical organizations, making it secondary data.
  • 2. Weights of students of our class: This data is collected directly by the teacher or an investigator from the students themselves, making it primary data.
  • 3. Production of wheat in the last 10 years: This information is typically obtained from agricultural reports or government statistics, hence it is secondary data.
  • 4. Number of plants in our locality: If collected by counting each plant in the locality, this would be primary data.
  • 5. Rainfall in our city in the last 10 years: This data is usually recorded by meteorological departments or weather stations, making it secondary data.

Question 1

The blood groups of 30 students of Class VIII are recorded as follows: A, B, O, O, AB, O, A, O, B, A, O, B, A, O, O, A, AB, O, A, A, O, O, AB, B, A, O, B, A, B, O. Represent this data in the form of a frequency distribution table. Which is the most common, and which is the rarest, blood group among these students?
Solution:

To represent the data in a frequency distribution table, we need to count the occurrences of each blood group among the 30 students.

Let's tally the blood groups:

  • Blood Group A: Tally marks |||| |||| (9 students)
  • Blood Group B: Tally marks |||| | (6 students)
  • Blood Group AB: Tally marks ||| (3 students)
  • Blood Group O: Tally marks |||| |||| | (12 students)

Now, we can construct the frequency distribution table:

Blood group Number of students (Frequency)
A 9
B 6
AB 3
O 12
Total 30

From the table, we can observe the frequencies of each blood group:

  • The highest frequency is 12, which corresponds to blood group O.
  • The lowest frequency is 3, which corresponds to blood group AB.

Therefore:

  • The most common blood group among these students is O.
  • The rarest blood group among these students is AB.

Common mistakes

  • Confusing primary and secondary data collection methods.
  • Errors in tallying and counting frequencies for data classification.
  • Incorrectly identifying the most common or rarest data points.

Revision tips

  • Practice collecting different types of data from your surroundings.
  • Create your own frequency tables for everyday observations.
  • Review the definitions of primary and secondary data to avoid confusion.
  • Pay close attention to the tally marks when constructing frequency tables.

Practice MCQs

Q1. Which type of data is collected directly by the investigator for a specific purpose?

Q2. Data collected from a source that has already published it is known as:

Q3. In a frequency distribution table, what does the frequency represent?

Q4. If 12 students have blood group O, and this is the highest count, then O is the:

Q5. If 3 students have blood group AB, and this is the lowest count, then AB is the:

Frequently asked questions

What is the main focus of Chapter 14 Statistics for Class 9?

Chapter 14 focuses on the fundamental concepts of statistics, including understanding data, differentiating between primary and secondary data, and organizing data using frequency distribution tables.

How do these NCERT Solutions help students?

These solutions provide clear, step-by-step explanations for each question, helping students understand the concepts of data collection and classification, and how to construct frequency tables accurately.

What is the difference between primary and secondary data?

Primary data is collected directly by the investigator for a specific purpose, while secondary data is collected from sources that have already gathered and published the information.

What is a frequency distribution table?

A frequency distribution table organizes data by showing how often each value or category appears in a dataset. It typically includes the data values, tally marks, and their corresponding frequencies.

How can I identify the most common and rarest blood group from the given data?

To find the most common blood group, look for the one with the highest frequency (number of students). To find the rarest, look for the one with the lowest frequency.

Important links

Content reviewed by the NCERT Help team. Editorial Team and update policy

NCERT Solutions PDF PDF on NCERT Help. URL unchanged for search indexing.