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Question
Draw an ogive for the following :
| Marks obtained | More than 10 | More than 20 | More than 30 | More than 40 | More than 50 |
| No. of students | 8 | 25 | 38 | 50 | 67 |
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Solution
Steps :
1. Start with lower limits of class intervals and from cumulative frequency , subtract the frequency of each class to obtain c.f distribution.
2. Mark lower class limits along x-axis. 1 cm = 5 units
3. Mark cumulative frequencies along y-axis. 1 cm = 5 units
4. Plot points (x,f) where x is the lower limit of one class and f is the corresponding c.f. (10,188),(20,180),(30,155),(40,117),(50,67)
5. Join the points to get the ogive.
| Marks more than | Frequency | Cumulative Frequency |
| 10 | 8 | 188 |
| 20 | 25 | 180 |
| 30 | 38 | 155 |
| 40 | 50 | 117 |
| 50 | 67 | 67 |
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