Class 11-commerce TR JAIN AND VK OHRI Solutions Statistics for Economics Chapter 4 - Organisation of Data

Organisation of Data Exercise 75

Solution SAQ 1

ii. Data with cumulative frequencies:

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

Solution SAQ 2

Data in the form of frequency distribution:

Solution SAQ 3

Individual series:

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

Cumulative frequency series:

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

Solution SAQ 4

Exclusive frequency distribution:

Organisation of Data Exercise 76

Solution SAQ 5

Frequency distribution:

Solution SAQ 6

Given data can be written as:

Marks	Cumulative Frequency (c.f)
Less than 3	5
Less than 6	12
Less than 9	25
Less than 12	33

Simple frequency distribution:

Marks	Frequency (f)
0 - 3	5
3 - 6	7 (= 12 - 5)
6 - 9	13(= 25 - 12)
9 - 12	8(= 33 - 25)
	∑f =33

Solution SAQ 7

Discrete series:

Solution SAQ 8

i. Frequency distribution:

Solution SAQ 9

Frequency distribution on exclusive basis:

Weight (in kg)	No. of students (f)
40 - 50	7
50 - 60	7
60 - 70	5
70 - 80	3
80 - 90	2
90 - 100	1
	∑f = 25

Frequency distribution on inclusive basis:

Weight (in kg)	No. of students (f)
40 - 50	9
51 - 61	6
62 - 72	6
73 - 83	2
84 - 94	2
95 - 105	0
	∑f = 25

Organisation of Data Exercise 77

Solution SAQ 10

Lower limits and upper limits of class intervals are calculated using the following formula.

where m is mid value and i is the difference between mid-values.

Mid-value	Class-interval	Frequency (f)
5	0 - 10	2
15	10 - 20	8
25	20 - 30	15
35	30 - 40	12
45	40 - 50	7
55	50 - 60	6
		∑f = 50

Solution SAQ 11