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Question
Given below is a cumulative frequency distribution showing the marks secured by 50 students of a class:
| Marks | Below 20 | Below 40 | Below 60 | Below 80 | Below 100 |
| Number of students | 17 | 22 | 29 | 37 | 50 |
Form the frequency distribution table for the data.
Solution
Here, we observe that, 17 students have scored marks below 20 i.e., it lies between class interval 0 – 20 and 22 students have scored marks below 40, so 22 – 17 = 5 students lies in the class interval 20 – 40 continuing in the same manner, we get the complete frequency distribution table for given data.
| Marks | Number of students |
| 0 – 20 | 17 |
| 20 – 40 | 22 – 17 = 5 |
| 40 – 60 | 29 – 22 = 7 |
| 60 – 80 | 37 – 29 = 8 |
| 80 – 100 | 50 – 37 = 13 |
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