Draw Histogram
| Class | Frequency |
| 10 - 20 | 15 |
| 20 - 30 | 25 |
| 30 - 40 | 20 |
| 40 - 50 | 12 |
| 50 - 60 | 8 |
| 60 - 70 | 5 |
| 70 - 80 | 3 |
Solution:To draw histogram, we first prepare the frequency distribution with boundary points, with central value of each class
| Class | Lower | Upper | Frequency `f` |
| 10 - 20 | 10 | 20 | 15 |
| 20 - 30 | 20 | 30 | 25 |
| 30 - 40 | 30 | 40 | 20 |
| 40 - 50 | 40 | 50 | 12 |
| 50 - 60 | 50 | 60 | 8 |
| 60 - 70 | 60 | 70 | 5 |
| 70 - 80 | 70 | 80 | 3 |
This material is intended as a summary. Use your textbook for detail explanation.
Any bug, improvement, feedback then