The frequency distribution :
Marks 0-20 20-40 40-60 60-100
Number of students 10 15 20 25
has been represented graphically as follows :
Do you think this representation is correct? Why?
Solution:
In the histogram, the width of rectangles are varying and we have to modify the lengths which makes the areas proportional to frequencies.
1. First select class interval with minimum class size, in the given data it is 20.
2. The rectangle length are modified to be proportionate to class size 20
The modified table is as follows
| Marks |
Number of students (Frequency) |
Width of the class | Length of the rectangle |
| 0-20 | 10 | 20 | 10/20 × 20 = 10 |
| 20-40 | 15 | 20 | 15/20 × 20 = 15 |
| 40-60 | 20 | 20 | 20/20 × 20 = 20 |
| 60-100 | 25 | 40 | 25/40 × 20 = 12.5 |
The correct histogram is mentioned below
Therefore, the representation is not correct and the modified one is mentioned above.
✦ Try This: Consider the data : 4, 5, 12, 16, 12, 5, 12. Since 16 is the highest value in the observations, is it correct to say that it is the mode of the data? Give reason.
☛ Also Check: NCERT Solutions for Class 9 Maths Chapter 14
NCERT Exemplar Class 9 Maths Exercise 14.2 Problem 1
The frequency distribution : Marks 0-20 20-40 40-60 60-100 Number of students 10 15 20 25 has been represented graphically as follows : Do you think this representation is correct? Why?
Summary:
The frequency distribution is represented graphically. The representation is not correct and the modified one is mentioned above
☛ Related Questions:
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