Example 3 - Chapter 14 Class 9 Statistics (Important Question)

Last updated at August 14, 2026 by

Example 3 - A teacher wanted to analyze the performance - Examples - Examples

part 2 - Example 3 - Examples - Serial order wise - Chapter 12 Class 9 Statistics
part 3 - Example 3 - Examples - Serial order wise - Chapter 12 Class 9 Statistics

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Transcript

Example 3 A teacher wanted to analyze the performance of two sections of students in a mathematics test of 100 marks. Looking at their performances, she found that a few students got under 20 marks and a few got 70 marks or above. So she decided to group them into intervals of varying sizes as follows: 0 - 20, 20 - 30, . . ., 60 - 70, 70 - 100. Then she formed the following table: Make histogram of the data The data has class intervals of varying width. So, we calculate adjusted frequency Adjusted frequency = (πΉπ‘Ÿπ‘’π‘žπ‘’π‘’π‘›π‘π‘¦ Γ— π‘…π‘’π‘žπ‘’π‘–π‘Ÿπ‘’π‘‘ 𝑠𝑖𝑧𝑒 π‘œπ‘“ π‘–π‘›π‘‘π‘’π‘Ÿπ‘£π‘Žπ‘™)/(πΆπ‘’π‘Ÿπ‘Ÿπ‘’π‘›π‘‘ 𝑠𝑖𝑧𝑒 π‘œπ‘“ π‘–π‘›π‘‘π‘’π‘Ÿπ‘£π‘Žπ‘™)

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