The class width in a histogram is determined by calculating the difference between the upper and lower limits of consecutive classes. This value should be consistent throughout the histogram.
Here's how to determine class width:
- Identify Consecutive Classes: Choose any two classes that are adjacent to each other.
- Determine Class Limits: For each selected class, find its upper and lower limits. These are the boundaries of each class as represented on the horizontal axis of the histogram.
- Calculate the Difference: Subtract the lower limit of one class from the lower limit of the consecutive class (or subtract the upper limit of one class from the upper limit of the consecutive class). This difference is the class width.
- For instance, using the example from the reference: if a class goes from 101 to 200, and the next class goes from 201 to 300, the class width would be 201-101 = 100 or 300-200 = 100.
| Class Range | Lower Limit | Upper Limit |
|-------------------|-------------|-------------|
| 101-200 | 101 | 200 |
| 201-300 | 201 | 300 |
| 301-400 | 301 | 400 |
| 401-500 | 401 | 500 |- Verify Consistency: Repeat this calculation with other consecutive classes. If the class widths are the same for all consecutive class pairs, then you have successfully calculated the class width for the histogram.
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According to the reference, a class width is the difference between consecutive lower limits of classes, and is consistently 100 for the given example.
- For instance, as shown in the reference, 201-101 = 100, and 301-201= 100
Therefore, the class width is consistent across the histogram.
