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Question
Draw an ogive for the following:
| Marks obtained | Less than 10 | Less than 20 | Less than 30 | Less than 40 | Less than 50 |
| No. of students | 8 | 22 | 48 | 60 | 75 |
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Solution
Steps:
1. On the x-axis, take 1 cm as 5 units and plot marks.
2. On the y-axis, take 1 cm as 5 units and plot frequency.
3. Plot the points with coordinates having abscissae as actual limits and ordinates as the cumulative frequencies. In this case (10, 8), (20, 22), (30, 48),(40, 60), (50, 75).
4. Join the points plotted by a smooth curve.
| Marks less than | Cumulative Frequency |
| 10 | 8 |
| 20 | 22 |
| 30 | 48 |
| 40 | 60 |
| 50 | 75 |

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