Class 8 SELINA Solutions Maths Chapter 23: Data Handling
Data Handling Exercise Ex. 23
Solution 1(i)
Correct option: (a) 15
The lower-class limit of 15 – 18 is 15.
Solution 1(ii)
Correct option: (b) 12.5
The lower-class limit of 5 – 12.5 is 12.5.
Solution 1(iii)
Correct option: (c) 13
Upper limit of a class interval = 16
Lower limit of a class interval = 10
Then,
Solution 1(iv)
Correct option: (a) 10
Upper limit of a class interval = 12.5
Lower limit of a class interval = 7.5
Then,
Solution 1(v)
Correct option: (a) 280
Central angle corresponding to 80 articles = 30°
That is,
Now, for central angle 105°,
Solution 1(vi)
Correct option: (c) 304
Central angle corresponding to 76 articles = 19°
That is,
Now, for central angle 76°,
Solution 2
The required bar graph is as follows:
Solution 3
Total monthly income = Rs. 7200
Savings = Rs. (7200 – 1800 – 2700 – 900 – 1200) = Rs. 600
| Name | Amount in Rs. | Central angle |
| Rent | 1800 |
|
| Food | 2700 |
|
| Education | 900 |
|
| Others | 1200 |
|
| Savings | 600 |
|
The pie-chart is as follows:
Solution 4
The bar graph is as follows:
Solution 5
|
Brands |
% Buyers |
Central angle |
|
A |
35 |
|
|
B |
20 |
|
|
C |
20 |
|
|
D |
15 |
|
|
Others |
10 |
|
|
|
100 |
360° |
The pie-chart is as follows:
Solution 6
The bar graph is as follows:
Solution 7
The bar graph is as follows:
Solution 8
The required bar graph is as follows:
Solution 9
| Subjects | Marks as percent | Central angle |
| Hindi | 60 |
|
| English | 45 |
|
| Maths | 42 |
|
| Science | 48 |
|
| Social Study | 75 |
|
|
| 270 | 360° |
The pie-chart is as follows:
Solution 10
The double bar graph is as follows:
Solution 11
The double bar graph is as follows:
Data Handling Exercise TEST YOURSELF
Solution 1(i)
Correct option: (c) frequency
The number of times a data, in the set, occurs is called frequency.
Solution 1(ii)
Correct option: (b) range
The difference between the greatest and the smallest values of observations is called range.
Solution 1(iii)
Correct option: (a) width of the class-interval
The difference between the upper and lower class-limits of a class-interval is called width of the class-interval.
Solution 1(iv)
Correct option: (d) frequency
In a bar-graph, if the widths of all the bars are kept same, their heights are proportional to their frequency.
Solution 1(v)
Correct option: (a) 
In a pie-chart, the angle corresponding to different components is given by 
.
Solution 2
The bar graph is as follows:
Solution 3
(i) Number of students in class VII = 60 + 40 = 100
Number of students in class VIII = 30 + 70 = 100
Number of students in class IX = 50 + 50 = 100
Therefore, classes VII, VIII and IX have the larger number of students.
(ii) Class IX has the equal number of girls and boys.
(iii) Number of students in class VIII = 30 + 70 = 100
(iv) Number of students in class VI = 30 + 50 = 80
Number of students in class VII = 60 + 40 = 100
Number of students in class VIII = 30 + 70 = 100
Number of students in class IX = 50 + 50 = 100
Number of students in class X = 60 + 30 = 90
Therefore, total number of students = 80 + 100 + 100 + 100 + 90 = 470
Solution 4
|
Class |
No. of students |
Central angle |
|
VI |
360 |
|
|
VII |
300 |
|
|
VIII |
54 |
|
|
IX |
150 |
|
|
X |
216 |
|
|
|
1080 |
360° |
The pie-graph is as follows:
Solution 5
Total number of students = 1080
|
Class |
Central angle |
No. of students |
|
VI |
65° |
|
|
VII |
90° |
|
|
VIII |
55° |
|
|
IX |
70° |
|
|
X |
80° |
|
|
|
360° |
1080 |
