TR Jain & Vk Ohri (2017) Solutions for Class 11 Science Economics Chapter 4 Organisation Of Data are provided here with simple step-by-step explanations. These solutions for Organisation Of Data are extremely popular among class 11 Science students for Economics Organisation Of Data Solutions come handy for quickly completing your homework and preparing for exams. All questions and answers from the TR Jain & Vk Ohri (2017) Book of class 11 Science Economics Chapter 4 are provided here for you for free. You will also love the ad-free experience on Meritnation’s TR Jain & Vk Ohri (2017) Solutions. All TR Jain & Vk Ohri (2017) Solutions for class 11 Science Economics are prepared by experts and are 100% accurate.

Page No 55:

Question 1:

Identify the following variables as discrete and continuous: volume, height, weight, temperature, snowfall, population, crop-production, no. of scooters on the ring road of Delhi, no. of houses demolished by the MCD.

Answer:

Discrete Variable Continuous Variable
1. Population 1. Volume
2. Crop-production 2. Height
3. No. of scooters on the ring road of Delhi 3. Weight
4. No. of houses demolished by the M.C.D 4. Temperature
    5. Snowfall



Page No 58:

Question 1:

Following data relate to the pocket expenses (rupees) of 10 students of Class XI. Arrange them in the ascending and descending orders:

50, 20, 30, 15, 45, 35, 40, 25, 20, 43.

Answer:

Data Arranged in Ascending Order Data Arranged in Descending Order
15
20
20
25
30
35
40
43
45
50
50
45
43
40
35
30
25
20
20
15

Page No 58:

Question 2:

In a sample investigation, 20 persons are found to have the following money in their pockets as office expenses. Arrange the data in the ascending and descending orders:

114, 108, 100, 98, 101, 109, 117, 119, 121, 136
131, 136, 143, 156, 169, 182, 195, 207, 219, 255.

Answer:

Data Arranged in Ascending Order Data Arranged in Descending Order
98
100
101
108
109
114
117
119
121
131
136
136
143
156
169
182
195
207
219
255
255
219
207
195
182
169
156
143
136
136
131
121
119
117
114
109
108
101
100
98

Page No 58:

Question 3:

Collect data of weekly expenditure on food by your family. Arrange the data in an order. Also, convert the data into monthly expenditure. Find the total number of observations.

Answer:



Data of weekly expenditure on food
 

Week Expenditure
1st week 1000
2nd week 2000
3rd week 2100
4th week 2200
5th week 2500
6th week 2700
7th week 2800
8th week 3000

Ascending and Descending order of data
 
Ascending order of data Descending order of data
1000 3000
2000 2800
2100 2700
2200 2500
2500 2200
2700 2100
2800 2000
3000 1000


Monthly Expenditure
 
Month Expenditure
1st Month 1000 + 2000 + 2100 + 2200 = Rs 7300
2nd Month 2500 + 2700 + 2800 + 3000 = Rs 11,000

Total number of observations = 8



Page No 75:

Question 1:

In an examination, 25 students secured the following marks:

23 28 30 32 35 35 36 40 41 43 44 45 45
48 49 52 53 54 56 56 58 61 62 65 68  
(i) Arrange these data in the form of a frequency distribution using the following class as intervals:
20−29, 30−39, 40−49, 50−59, and 60−69.
(ii) Arrange the data with cumulative frequencies.

Answer:


i) In the form of a frequency distribution, the given data can be arranged as follows.


ii) With cumulative frequencies the given data can be arranged as follows.

METHOD-1 METHOD-2
Marks No. of Students Marks No. of students
Less than 29
Less than 39
Less than 49
Less than 59
Less than 69
0 + 2 = 2
2 + 5 = 7
7 + 8 = 15
15 + 6 = 21
21 + 4 = 25
More than 20
More than 30
More than 40
More than 50
More than 60
25
25 − 2 = 23
23 − 5 = 18
18 − 8 = 10
10 − 6 = 4

Page No 75:

Question 2:

The following data is of the age of 25 students of Class XI.
Arrange these data in the form of a frequency distribution.

15 16 16 17 18 18 17 15 15 16 16 17 15
16 15 16 16 18 15 17 17 18 10 16 15  

Answer:

Page No 75:

Question 3:

Students of Class XI obtained following marks in Economics. Classify the data in the form of individual series, discrete series, continuous series and cumulative frequency series.

15 15 18 16 20 21 25 25 15 16 18 22 24 25 20
18 22 24 24 25 25 23 20 15 16 17 19 18 22 22

Answer:

Individual series is simply the arrangement of the given data in ascending (or, descending order)
 

15 15 15 15 16 16 16 17 18 18 18 18 19 20 20
20 21 22 22 22 22 23 24 24 24 25 25 25 25 25


Discrete series:


Continuous series:


Cumulative frequency series

Method1 Method2
Marks No. of Students Marks No. of students
Less than 15
Less than 19
Less than 23
Less than 27
0
9 + 4 = 13
13 + 9 = 22
22 + 8 = 30
More than 12
More than 16
More than 20
More than 24
30
30 − 4 = 26
26 − 9 = 17
17 − 9 = 8

Page No 75:

Question 4:

Arrange the following data in the form of an exclusive frequency distribution, using 5−10 as the initial class interval:

12 36 40 30 28 20 19 10 10 19 27 15 26 10
19 7 45 33 26 37 5 20 11 17 37 30 20  

Answer:



Page No 76:

Question 5:

Weight of 20 students is given in kilograms. Using class interval of 5, make a frequency distribution.

30 45 26 25 42 33 15 35 45 45
45 39 42 40 18 35 41 20 36 48

Answer:

In the given data, the lowest value is 15, while the highest value is 48. Accordingly, we take (15 - 20) as the initial class interval.

Weight (kg) Tally Bars No. of Students
15−20 2
20−25 1
25−30 2
30−35 2
35−40 4
40−45 4
45−50 5
Total   f=20

Page No 76:

Question 6:

Convert the following data in a simple frequency distribution:

5 students obtained less than 3 marks
12 students obtained less than 6 marks
25 students obtained less than 9 marks
33 students obtained less than 12 marks

Answer:

The given information can be summarised as follows.
 

Marks  Cumulative Frequency
(c.f.)
Less than 3
Less than 6
Less than 9
Less than 12
5
12
25
33
This can be presented in the form of a simple frequency distribution as follows.
 
Marks   Frequency
(f)
3
3  6
6 − 9
 9 − 12
5
7 (= 12 5)
13 (= 25 12)
8 (= 33 25)
  Σf =33

Page No 76:

Question 7:

In the following statement, take the number of letters in a word as items and number of items a word (of the same size) repeats itself as frequencies. Prepare a discrete series.
"Success in the examination confers no absolute right to appointment unless government is satisfied after such an enquiry as may be considered necessary that the candidate is suitable in all respect for appointment."

Answer:

In the given question, the size of the items refers to the number of alphabets in the word. Accordingly, in the given statement there are eight items with size equal to 2, namely, in, no, to, is, an, as, be, is, in. Similarly, there are 5 items with size equal to three, namely, the, may, the, all, for.  In the similar manner, we can find the frequency corresponding to the various items. 
The frequency distribution table is prepared in the following manner.
 

Size of Item Tally Bars Frequency
2 9
3 5
4 2
5 2
6 1
7 3
8 3
9 3
10 2
11 3
Total   f=33




 

Page No 76:

Question 8:

An economic survey revealed that 30 families in a town incur following expenditure in a day (rupees).

11 12 14 16 16 17 18 18 20 20 20 21 21 22 22
23 23 24 25 25 26 27 28 28 31 32 32 33 36 38
(i) Convert these data in the form of a frequency distribution, using the following class intervals.
10−14, 15−19, 20−24, 25−29, 30−34 and 35−39.
(ii) How many families spend more than 29 rupees a day?

Answer:

i)


ii) Number of families spending more than Rs 29 per day = 4+2 = 6
Thus, there are 6 families that spend more than Rs 29 per day.

Percentage of families spending more than Rs 29
=Number of families spending more than Rs 29Total number of families×100= 630×100=20%Thus, 20% of the families spend more than Rs 29 per day.

Page No 76:

Question 9:

From the following data related to the weight of college students in kg, prepare a frequency distribution with a class interval of 10 exclusive and inclusive basis:

40

92

49

52

69
70

72

42

50

60
63

65

43

48

54
53

53

47

65

82
85

79

50

42

55

Answer:

Exclusive Method Inclusive Method
Weight
(in kg)
No. of Students
(f)
Weight
(in kg)
No. of Students
(f)
40 − 50
50 − 60
60 − 70
70 − 80
80 − 90
90 − 100
7
7
5
3
2
1
40 − 50
51 − 61
62 − 72
73 − 83
84 − 94
95 − 105
9
6
6
2
2
0
  f = 25   f = 25



Page No 77:

Question 10:

Construct the simple frequency distribution from the following data:

Mid-value 5 15 25 35 45 55
Frequency 2 8 15 12 7 6

Answer:

The class interval can be calculated from the mid-points using the following adjustment formula. 

The value obtained is then added to the mid point to obtain the upper limit and subtracted from the mid-point to obtain the lower limit.

For the given data, the class interval is calculated by the following value of adjustment.

 

Thus, we add and subtract 5 to each mid-point to obtain the class interval.

For instance:

The lower limit of first class = 5 – 5 = 0

Upper limit of first class = 5 + 5 = 10

Thus, the first class interval is (0 − 10). Similarly, we can calculate the remaining class intervals.
 

Mid-value Class-interval Frequency
(f)
5
15
25
35
45
55
 10
10  20
20  30
30  40
40  50
50  60
2
8
15
12
7
6
    f = 50

Page No 77:

Question 11:

Classify the following data by taking class interval such that their mid-values are 17, 22, 27, 32 and so on:

30

30

36

33
42

27

22

41
30

42

30

21
54

36

31

16
40

28

19

17
48

28

48

36
14

37

16

37
17

54

42

41
51

44

32

46
42

31

21

47
25

36

22

52
41

40

40

53

Answer:

The class interval can be calculated from the mid-points using the following adjustment formula. 

The value obtained is then added to the mid point to obtain the upper limit and subtracted from the mid-point to obtain the lower limit.

For the given data, the class interval is calculated by the following value of adjustment.
Value of adjustment = 17 - 122= 2.5

Thus, we add and subtract 2.5 to each mid-point to obtain the class interval.

For instance:

The lower limit of first class = 12 – 2.5 = 9.5

Upper limit of first class = 12 + 2.5 = 14.5

Thus, the first class interval is (9.5  14.5). Similarly, we can calculate the remaining class intervals.
 

Mid-value Class-interval Frequency
(f)
12
17
22
27
32
37
42
47
52
9.5  14.5
14.5  19.5
19.5  24.5
24.5  29.5
29.5  34.5
34.5  39.5
39.5  44.5
44.5  49.5
49.5  54.5
1
5
4
4
8
6
11
4
5
    f = 48



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