Estimate probabilities from grouped continuous frequency data
These observations are grouped by class interval for lifetimes measured for a group of components
Let X denote the quantity in the table, measured in hours
| Class interval (hours) | Frequency |
|---|---|
| \(0\le x < 10\) | 38 |
| \(10\le x < 20\) | 31 |
| \(20\le x < 30\) | 24 |
| \(30\le x < 40\) | 17 |
| \(40\le x < 50\) | 10 |
Use the grouped table as an approximate probability model. The table assigns frequencies to whole class intervals. At a class boundary, changing strict to non-strict endpoint notation does not change the class count
The event to use is \(30 < X \le 40\)