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Question
The marks of 200 students in a test were recorded as follows:
| Marks % |
0-10 | 10-20 | 20-30 | 30-40 | 40-50 | 50-60 | 60-70 | 70-80 | 80-90 | 90-100 |
| No. of students |
5 | 7 | 11 | 20 | 40 | 52 | 36 | 15 | 9 | 5 |
Using graph sheet draw ogive for the given data and use it to find the,
- median,
- number of students who obtained more than 65% marks
- number of students who did not pass, if the pass percentage was 35.
Solution
| Marks (%) | f | cf |
| 0 – 10 | 5 | 5 |
| 10 – 20 | 7 | 12 |
| 20 – 30 | 11 | 23 |
| 30 – 40 | 20 | 43 |
| 40 – 50 | 40 | 83 |
| 50 – 60 | 52 | 135 |
| 60 – 70 | 36 | 171 |
| 70 – 80 | 15 | 186 |
| 80 – 90 | 09 | 195 |
| 90 – 100 | 05 | 200 |
- Median = 53 ± 1
- More than 65% = 46 ± 2
- Didn't pass = 31 ± 2
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10 | 20 | 30 | 40 | 50 | 60 | 70 | 80 | 90 | 100 |
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(2)the quartile marks.
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| Marks | No. of students |
| 0 – 9 | 5 |
| 10 – 19 | 9 |
| 20 – 29 | 16 |
| 30 – 39 | 22 |
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