हिंदी

The frequency distribution has been represented graphically as follows: Marks 0 – 20 20 – 40 40 – 60 60 – 100 Number of Students 10 15 20 25 Do you think this representation is correct? Why?

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प्रश्न

The frequency distribution has been represented graphically as follows:

Marks 0 – 20  20 – 40 40 – 60 60 – 100
Number of Students 10 15 20 25


Do you think this representation is correct? Why?

आलेख
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उत्तर

No, here the widths of the rectangles are varying, so we need to make certain modifications in the length of the rectangles so that the areas are proportional to the frequencies.

We proceed as follows:

1. Select a class interval with the minimum class size, here the minimum class size is 20.

2. The length of the rectangles are then modified to be proportionate to the class size 20.

Now, we get the following modified table:

Marks Number of students
(Frequency)
Width of the
class
Length of the
rectangle
0 – 20 10 20 `10/20 xx 20 = 10`
20 – 40 15 20 `15/20 xx 20 = 15`
40 – 60 20 20 `20/20 xx 20 = 20`
60 – 100 25 40 `25/40 xx 20 = 12.5`

So, the correct histogram with varying width is given below:

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  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
अध्याय 14: Statistics & Probability - Exercise 14.2 [पृष्ठ १३६]

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एनसीईआरटी एक्झांप्लर Mathematics Exemplar [English] Class 9
अध्याय 14 Statistics & Probability
Exercise 14.2 | Q 1. | पृष्ठ १३६

वीडियो ट्यूटोरियलVIEW ALL [2]

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