1. **State the problem:** We have temperature data recorded over 30 days, grouped into intervals with the number of days each temperature range was recorded. We need to find the interval containing the median temperature. 2. **Understand the median:** The median is the middle value when all data points are ordered. For 30 days, the median is the average of the 15th and 16th values. 3. **List the intervals and frequencies:** - 31–40°F: 0 days - 41–50°F: 1 day - 51–60°F: 2 days - 61–70°F: 3 days - 71–80°F: 4 days - 81–90°F: 6 days 4. **Calculate cumulative frequencies:** - Up to 40°F: 0 days - Up to 50°F: 0 + 1 = 1 day - Up to 60°F: 1 + 2 = 3 days - Up to 70°F: 3 + 3 = 6 days - Up to 80°F: 6 + 4 = 10 days - Up to 90°F: 10 + 6 = 16 days 5. **Locate the median position:** The 15th and 16th days fall in the cumulative frequency range between 10 and 16 days, which corresponds to the 81–90°F interval. 6. **Conclusion:** The median temperature lies in the interval **81–90°F**.