How do you calculate cumulative frequency from a histogram?

To calculate cumulative frequency from a histogram, add the frequencies of each class interval sequentially.

In more detail, a histogram is a type of bar chart that represents the frequency of data within certain intervals, known as class intervals or bins. To find the cumulative frequency, you need to sum the frequencies of the class intervals in a step-by-step manner.

Start with the first class interval on the histogram. The frequency of this interval is your initial cumulative frequency. For the next class interval, add its frequency to the cumulative frequency of the previous interval. Continue this process for each subsequent class interval. Essentially, you are adding the frequency of each interval to the total of all previous frequencies.

For example, if your histogram has class intervals with frequencies of 5, 7, 3, and 10, the cumulative frequency calculation would be as follows:
- The first interval has a frequency of 5, so the cumulative frequency is 5.
- The second interval has a frequency of 7. Add this to the previous cumulative frequency (5), resulting in a cumulative frequency of 12.
- The third interval has a frequency of 3. Add this to the previous cumulative frequency (12), resulting in a cumulative frequency of 15.
- The fourth interval has a frequency of 10. Add this to the previous cumulative frequency (15), resulting in a cumulative frequency of 25.

By the end of this process, you will have a cumulative frequency for each class interval, which helps in understanding the distribution of data across the intervals.