Class 9 Exam  >  Class 9 Notes  >  RD Sharma Solutions for Class 9 Mathematics  >  RD Sharma Solutions -Ex-22.2, Tabular Representation Of Statistical Data, Class 9, Maths

Ex-22.2, Tabular Representation Of Statistical Data, Class 9, Maths RD Sharma Solutions | RD Sharma Solutions for Class 9 Mathematics PDF Download

Q1. Define cumulative frequency distribution.

Solution 1: Cumulative frequency distribution:

A table which displays the manner in which cumulative frequencies are distributed over various classes is called a cumulative frequency distribution or cumulative frequency distribution table.

 

Q2. Explain the difference between a frequency distribution and a cumulative frequency distribution.

Solution 2:

Frequency table or frequency distribution is a method to represent raw data in the form from which one can easily understand the information contained in a raw data, where as a table which plays the manner in which cumulative frequencies are distributed over various classes is called a cumulative frequency distribution.

 

Q3. The marks scored by 55 students in a test are given below:

Marks0 - 55 - 1010 - 1515 - 2020 - 2525 - 3030 - 35
No. of students2613171142

Prepare a cumulative frequency table

Solution 3:

MarksNo. of studentsMarksCumulative Frequency
0 - 52Less than 52
5 - 106Less than 108
10 - 1513Less than 1521
15 - 2017Less than 2038
20 - 2511Less than 2549
25 - 304Less than 3053
30 - 352Less than 3555
 N = 55  

 

Q4. Following are the ages of 360 patients getting medical treatment in a hospital on a day.

Age(in years)10 - 2020 - 3030 - 4040 - 5050 - 6060 - 70
No of patients905060805030

Construct a cumulative frequency table.

Solution 4:

Age (in years)No. of studentsMarksCumulative Frequency
10 - 2090Less than 2090
20 - 3050Less than 30140
30 - 4060Less than 40200
40 - 5080Less than 50280
50 - 6050Less than 60330
60 - 7030Less than 70360
 N = 360  

 

Q5. The water bills (in rupees) of 32 houses in a certain street for the period 1.198 to 31.398 are given below:

56,43,32,38,56,24,68,85,52,47,35,58,63,74,27,84,69,35,44,75,55,30,54,65,45,67,95,72,43,65,35,69.

Tabulate the data and present the data as a cumulative frequency table using 70 - 79 as one of the class intervals.

Solution 5:

The minimum bill is Rs 24

The maximum bill is Rs 95

Range = Maximum bill - Minimum bill = 95 - 24 = 71

Given class interval is 70 - 79.So, class size = 79 - 70 = 9

Therefore number of classes =  Ex-22.2, Tabular Representation Of Statistical Data, Class 9, Maths RD Sharma Solutions | RD Sharma Solutions for Class 9 Mathematics

Number of classes = 8

The cumulative frequency distribution is as follows:

BillsNo. of houses(frequency)Cumulative frequency
16 - 2511
25 - 3434
34 - 4359
43 - 52413
52 - 61720
61 - 70626
70 - 79329
79 - 88231
88 - 97132

 

Q6.The number of books in different shelves of a library is as follows:

30, 32, 28, 24, 20, 25, 38, 37, 40, 45, 16, 20

19, 24, 27, 30, 32, 34, 35, 42, 27, 28, 19, 34

38, 39, 42, 29, 24, 27, 22, 29, 31, 19, 27, 25

28, 23, 24, 32, 34, 18, 27, 25, 37, 31, 24, 23

43, 32, 28, 31, 24, 23, 26, 36, 32, 29, 28, 21.

Prepare a cumulative frequency distribution table using 45 - 49 as the last class - interval.

Solution 6:

The minimum number of bookshelves is 16

and maximum number of bookshelves is 45

Range = Maximum book shelves - Minimum book shelves = 45 - 16 = 29

Given class interval is 45 - 49.So, class size = 49 - 45 = 4

Therefore number of classes =  Ex-22.2, Tabular Representation Of Statistical Data, Class 9, Maths RD Sharma Solutions | RD Sharma Solutions for Class 9 Mathematics

Number of classes = 8

The cumulative frequency distribution is as follows:

No of booksNo. of shelves(frequency)Cumulative frequency
13 - 1711
17 - 2167
21 - 251118
25 - 291533
29 - 331245
33 - 37550
37 - 41656
41 - 45359
45 - 49160

 

Q7. Given below are the cumulative frequencies showing the weights of 685 students of a school. Prepare a frequency distribution table.

Weight(in kg)No. of students
Below 300
Below 3024
Below 3578
Below 40183
Below 45294
Below 50408
Below 55543
Below 60621
Below 65674
Below 70685

Solution 7:

Weight(in kg)No. of studentsClass intervalfrequency
Below 302425 - 3024 - 0 = 24
Below 357830 - 3578 - 24 = 54
Below 4018335 - 40183 - 78 = 105
Below 4529440 - 45294 - 183 = 111
Below 5040845 - 50408 - 294 = 114
Below 5554350 - 55543 - 408 = 135
Below 6062155 - 60621 - 543 = 78
Below 6567460 - 65671 - 621 = 53
Below 7068565 - 70685 - 671 = 11

 

Q8. The following cumulative frequency distribution table shows the daily electricity consumption (in KW) of 40 factories in an industrial state.

Consumption(in KW)No. of factories
Below 2401
Below  2704
Below 3008
Below 33024
Below 36033
Below 39038
Below 42040

(1) Represent this as a frequency distribution table.

(2)Prepare a cumulative frequency table.

Solution 8:

(1)

Consumption(in KW)No. of factoriesClass intervalFrequency
Below 24010 - 2401
Below  2704240 - 2704 - 1 = 3
Below 3008270 - 3008 - 4 = 4
Below 33024300 - 33024 - 8 = 16
Below 36033330 - 36033 - 24 = 9
Below 39038360 - 39038 - 33 = 5
Below 42040390 - 42040 - 38 = 2

(2)

Class intervalFrequencyConsumption(in KW)No. of factories
0 - 2401More than 040
240 - 2703More than 24040 - 1 = 39
270 - 3004More than 27039 - 3 = 36
300 - 33016More than 30036 - 4 = 32
330 - 3609More than 33032 - 16 = 16
360 - 3905More than 36016 - 9 = 7
390 - 4202More than 3907 - 5 = 2
  More than 4202 - 2 = 0
 N = 40  

 

Q9. Given below is a cumulative frequency distribution table showing ages of the people living in a locality:

Age in yearsNo. of years
Above 1080
Above 961
Above 843
Above  725
Above 6020
Above 48158
Above 36427
Above 24809
Above 121026
Above 01124

Prepare a frequency distribution table.

Solution 9:

Age (in years)No. of personsClass intervalFrequency
Above 011240 - 121124 - 1026 = 98
Above 12102612 - 24217
Above 2480924 - 36382
Above  3642736 - 48269
Above 3815848 - 60138
Above 602060 - 7215
Above 72572 - 845 - 3 = 2
Above 84384 - 963 - 1 = 2
Above 96396 - 1081 - 0 = 1
The document Ex-22.2, Tabular Representation Of Statistical Data, Class 9, Maths RD Sharma Solutions | RD Sharma Solutions for Class 9 Mathematics is a part of the Class 9 Course RD Sharma Solutions for Class 9 Mathematics.
All you need of Class 9 at this link: Class 9
91 docs

Top Courses for Class 9

FAQs on Ex-22.2, Tabular Representation Of Statistical Data, Class 9, Maths RD Sharma Solutions - RD Sharma Solutions for Class 9 Mathematics

1. What is the importance of tabular representation of statistical data?
Ans. Tabular representation of statistical data is important because it helps in organizing and summarizing large amounts of data in a systematic manner. It allows for easy comparison and analysis of different sets of data. Additionally, it helps in identifying patterns, trends, and outliers in the data, which is crucial for making informed decisions and drawing meaningful conclusions.
2. How can I construct a frequency distribution table from raw data?
Ans. To construct a frequency distribution table from raw data, follow these steps: 1. Determine the range of the data by subtracting the smallest value from the largest value. 2. Decide on the number of classes or intervals you want to divide the data into. Generally, it is recommended to have around 5-15 classes. 3. Calculate the width of each class by dividing the range by the number of classes and rounding it off to a convenient number. 4. Create a table with columns for the classes, frequencies, and cumulative frequencies. 5. Start with the lowest value and assign each data point to the respective class interval. 6. Count the number of data points in each class and record the frequencies in the table. 7. Calculate the cumulative frequencies by adding up the frequencies from the first class to each subsequent class. 8. Finally, you have your frequency distribution table ready for further analysis.
3. How can I calculate the mean using a frequency distribution table?
Ans. To calculate the mean using a frequency distribution table, use the following steps: 1. Multiply each class midpoint by its corresponding frequency. 2. Sum up the products obtained in step 1. 3. Divide the sum by the total number of data points (sum of frequencies). 4. The result is the mean or average value of the data.
4. What is the difference between a class interval and class frequency?
Ans. A class interval refers to the range of values that are grouped together in a frequency distribution table. It is represented by the lower class limit and the upper class limit. For example, if the class interval is 20-30, it means that all values between 20 and 30 (including 20 but excluding 30) are grouped together. On the other hand, class frequency refers to the number of data points that fall within a particular class interval. It represents the count or frequency of occurrence of values within that interval. It is recorded in the frequency column of a frequency distribution table.
5. How can I calculate the median from a grouped frequency distribution table?
Ans. To calculate the median from a grouped frequency distribution table, follow these steps: 1. Find the cumulative frequency just greater than or equal to (n/2), where n is the total number of data points. 2. Identify the corresponding class interval. 3. Use the formula: Median = L + ((n/2 - CF) * h) / f where L is the lower class limit of the median class interval, CF is the cumulative frequency of the class interval preceding the median class, h is the class width, and f is the frequency of the median class interval. 4. Substitute the values from the table into the formula to calculate the median.
91 docs
Download as PDF
Explore Courses for Class 9 exam

Top Courses for Class 9

Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
10M+ students study on EduRev
Related Searches

Sample Paper

,

pdf

,

Class 9

,

Objective type Questions

,

video lectures

,

Viva Questions

,

MCQs

,

Class 9

,

Maths RD Sharma Solutions | RD Sharma Solutions for Class 9 Mathematics

,

shortcuts and tricks

,

Semester Notes

,

Summary

,

Maths RD Sharma Solutions | RD Sharma Solutions for Class 9 Mathematics

,

Exam

,

Extra Questions

,

Class 9

,

past year papers

,

Free

,

Ex-22.2

,

Important questions

,

Tabular Representation Of Statistical Data

,

Tabular Representation Of Statistical Data

,

study material

,

Maths RD Sharma Solutions | RD Sharma Solutions for Class 9 Mathematics

,

Tabular Representation Of Statistical Data

,

Ex-22.2

,

mock tests for examination

,

practice quizzes

,

Previous Year Questions with Solutions

,

ppt

,

Ex-22.2

;