1. The problem is to understand the concept of a class interval in statistics. 2. A class interval is a range of values used to group data points in a frequency distribution. 3. For example, if we have data on ages, class intervals might be 0-9, 10-19, 20-29, etc. 4. Each class interval has a lower limit and an upper limit, and all data points within that range are counted in the frequency for that interval. 5. This helps organize data into manageable groups for analysis and visualization. 6. There is no calculation here, just understanding the definition and use of class intervals.