Chapter 14 Class 9 Statistics
Question 1 Important Deleted for CBSE Board 2024 Exams
Example 3 Important You are here
Example 4 Important
Ex 12.1, 4 Important
Ex 12.1, 7 Important
Question 1 Important Deleted for CBSE Board 2024 Exams
Question 3 Important Deleted for CBSE Board 2024 Exams
Question 5 Important Deleted for CBSE Board 2024 Exams
Question 6 (i) Important Deleted for CBSE Board 2024 Exams
Chapter 14 Class 9 Statistics
Last updated at April 16, 2024 by Teachoo
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 = (𝐹𝑟𝑒𝑞𝑢𝑒𝑛𝑐𝑦 × 𝑅𝑒𝑞𝑢𝑖𝑟𝑒𝑑 𝑠𝑖𝑧𝑒 𝑜𝑓 𝑖𝑛𝑡𝑒𝑟𝑣𝑎𝑙)/(𝐶𝑢𝑟𝑟𝑒𝑛𝑡 𝑠𝑖𝑧𝑒 𝑜𝑓 𝑖𝑛𝑡𝑒𝑟𝑣𝑎𝑙)