1. Let's start by defining grouped data and ungrouped data. 2. Ungrouped data refers to data collected in raw form without any categorization. For example, the ages of 5 people: 21, 23, 20, 22, 21. 3. Grouped data organizes raw data into groups or classes. For example, grouping ages into intervals: 20-21, 22-23, with frequencies of each group. 4. Practice question: Given the ungrouped data set of test scores: 55, 60, 65, 70, 75, 80, 85, 90, 95, 100. 5. Task 1: Group the data into class intervals of 55-64, 65-74, 75-84, 85-94, and 95-104. 6. Task 2: Determine the frequency of each class interval. 7. Solution step for Task 1: The classes are 55-64, 65-74, 75-84, 85-94, 95-104 as given. 8. Solution step for Task 2: Count the number of data points in each interval: - 55-64: 55, 60 (2 data points) - 65-74: 65, 70 (2 data points) - 75-84: 75, 80 (2 data points) - 85-94: 85, 90 (2 data points) - 95-104: 95, 100 (2 data points) Thus, frequencies for each grouped interval are 2.