NCERT Solutions for Class 11 Maths Chapter 15 Statistics


Statistics Class 11 NCERT solutions encompass one of the most important chapters in CBSE class 11 Mathematics. Students are likely to be introduced to these topics for the first time, which makes it all the more important for the basic concepts to be clear in the first instance itself.


Statistics Class 11 NCERT solutions familiarise students with the procedure to solve the sums that come from this chapter. It enables students to understand the different patterns of questions that may come in the examination. The marks weightage and distribution are elaborated as well in the solutions. Statistics Class 11 NCERT solutions PDF download can be easily downloaded from CoolGyan App completely free.

Class 11 Maths NCERT Solutions Chapter 15

Class 11 Maths Ch 15 NCERT Solutions shows the sums on a step-by-step basis. The concepts touched up in the chapter and the example sums are indicated below:

Mean Deviation About Mean

  1. Ungrouped

Example: Finding mean deviation about the mean of 6, 7, 10, 12, 13, 12, 8, 4

  1. Discrete Frequency

Example: Finding mean deviation about the mean of the below data:


xi

2

5

6

8

10

12

fi

2

8

10

7

8

5


  1. Continuous Frequency Distribution

Example: Finding the mean deviation about the mean of the below data:


Obtained Marks

Number of Students (fi)

Mid-point

(xi)

fixi

10-20

2

(10+20)/2 = 15

2 x 15 = 30

20-30

3

15+10 = 25

3 x 25 = 75

30-40

8

35

8 x 35 = 280

45-50

14

45

14 x 45 = 630

50-60

8

55

8 x 55 = 440

60-70

3

65

3 x 65 = 195

70-80

2

75

2 x 75 = 150


  • Mean Deviation About Median

  1. Ungrouped

Example: Finding the mean deviation about the median of 3, 5, 9, 3, 10, 12, 4, 18, 7, 19, 21

  1. Discrete Frequency

Example: Finding mean deviation about the median of the below data:


xi

3

6

9

12

13

15

21

22

fi

3

4

5

2

4

5

4

3


  1. Continuous Frequency Distribution

Example: Calculation of the mean deviation about median of the below data:

Class

0-10

10-20

20-30

30-40

40-50

50-60

Frequency

6

7

15

16

4

2


  • Standard Deviation and Variance

  1. Ungrouped Data

Example: Finding the variance of 6, 8, 10, 12, 14, 16, 18, 20, 22, 24

  1. Discrete Frequency

Example: Finding the variance and standard deviation of the below data:

xi

4

8

11

17

20

24

32

fi

3

5

9

5

4

4

1


  1. Continuous Frequency

Example: Calculation of the mean, variance and standard deviation of the following distribution: 

Class

30-40

40-50

50-60

60-70

70-80

80-90

90-100

Frequency (fi)

3

7

12

15

8

3

2


  • Coefficient of Variation

Example: Determine which group is more variable from the below data:

Marks

10-20

20-30

30-40

40-50

50-60

60-70

70-80

Group M

9

17

32

33

40

10

9

Group N

10

20

30

25

43

15

7


  • Indirect Questions

  1. Multiplication of Observation

Example: Given that the mean and standard deviation of six observations are 8 and 4 respectively, if each observation is multiplied by 3, what would be the new mean and new standard deviation of the resultant observations?

  1. Finding Remaining Observations

Example: The variance and mean of 7 observations are 16 and 8 respectively. If 5 of the observations amount to 2, 4, 10, 12, 14, what are the remaining 2 observations?

  1. Incorrect Observation

Example: The standard deviation and mean of 100 observations are 5.1 and 40 respectively. However, a mistake was detected in case of one observation where instead of 40, 50 was taken. What would be the correct standard deviation and mean?


We cover all exercises in the chapter given below:- 

Exercise 15.1 - 20 Questions with Solutions

Exercise 15.2 - 10 Questions with Solutions

Exercise 15.3 - 5 Questions with Solutions.


How is Statistics Class 11 Maths NCERT PDF Advantageous to Students?

Preparation of Class 11 Maths Statistics requires a higher degree of dedication and diligence from students. In that respect, Class 11 Maths Statistics solutions facilitates the process for students. Here are few of the prominent reasons why the solutions are advantageous:

  1. In-Depth Content With Lucid Language: Class 11 Statistics solutions discuss the topics in an elaborate manner, and at the same ensures that it is done in a simple language.

  2. Follow Approved Curriculum: Class 11 Maths chapter 15 solutions strictly adheres to the CBSE curriculum. Hence, these solutions itself form the base for board examination preparation. 

  3. Explanation of Fundamental Concepts: Before proceeding on to advanced topics, basic concepts are dealt with in an exhaustive manner so that doubts or confusion of students may get clarified.

So, wait no more and download NCERT solutions for Class 11 Maths Chapter 15 Statistics from CoolGyan portal now!

FAQs (Frequently Asked Questions)

Q1. What are the Different Sub-Topics of Chapter 15 Maths Class 11?

Ans. The sub-topics of Ch 15 Maths Class 11 include:

  1. Measure of Dispersion

  2. Range

  3. Mean Deviation

  4. Variance and Standard Deviation

  5. Frequency Distribution Analysis.

Q2. What is Understood by Standard Deviation?

Ans. Standard deviation in solution of Statistics Class 11 deals with the measurement of the amount of dispersion or variation of a given set of values. Depending on the level of standard deviation, the range is determined.

Q3. Why are Class 11 Maths Chapter 15 NCERT Solutions Useful to Students?

Ans. Class 11 Statistics NCERT solutions include accurate explanation to the problems and also, it is indicated in a step-by-step method. It becomes easier for students to understand how to understand similar questions.

Q4. What are the topics discussed in Chapter 15 of NCERT Solutions for Class 11 Maths?

Ans: Chapter 15 of NCERT Solutions for Class 11 Maths is Statistics. It is the branch that deals with the collection, organization, and interpretation of data. This chapter talks about the concept of central tendency, mean and median. You can find the NCERT Solutions Class 11 Maths Chapter 15 on CoolGyan. It will help you clear your doubts and concepts.

Q5. What are the important formulae of Statistics Class 11?

Ans: Formulae of mean, median, variance and standard deviation are important in Class 11. Once you finish them, you will be able to develop an explicit understanding of the topics covered in the CBSE Class 11 Maths syllabus. To do this, you need to solve and practice each sum from the examples and exercises given in the NCERT Class 11 Maths CBSE book. You can find the solutions for these exercises in CoolGyan’s NCERT Solutions for Class 11 Maths Statistics. The solutions are free.

Q6. Name the important concepts discussed in Chapter 15 of NCERT Solutions for Class 11 Maths.

Ans: CoolGyan offers study material designed in a simple, straightforward language, which is easy to memorise. Chapter 15, Statistics, provides you with an idea of graphs, histograms, pie charts and bar graphs. It works on your analytical skills. Relevant diagrams, graphs, illustrations are provided along with the answers wherever required. 

Q8. How can I make a Study Plan for Class 11?

Ans: You may find Class 11 a little difficult as you are introduced to new streams and subjects. It may be messy to dwell in the new study pattern because it requires hard and smart work both to achieve good marks in exams. Setting a routine and working according to it, and dividing the time for study and relaxing will help you. You need to cut off the distractions and focus on studies to excel in exams. Use the CoolGyan Mobile app for better comfort and portability.