Which type of frequency distribution would best summarize the distribution of number of hours worked by volunteers in a community project?

• A. A pie chart showing the proportion of volunteers by gender
• B. A frequency distribution of categorical data such as favorite color
• C. A scatterplot of age versus income
• D. A grouped frequency distribution with class intervals representing ranges of hours worked

Answer: (D)

Verified step by step guidance

1. Identify the type of data involved: The number of hours worked by volunteers is quantitative (numerical) data, which can take a range of values.
2. Understand that for quantitative data, especially when values cover a wide range, it is useful to group the data into intervals or classes to summarize it effectively.
3. A grouped frequency distribution organizes the data into class intervals (e.g., 0-5 hours, 6-10 hours, etc.) and counts how many observations fall into each interval.
4. This method helps to see the overall pattern or distribution of hours worked, such as where most volunteers fall in terms of hours contributed.
5. Other options like pie charts for categorical data or scatterplots for relationships between two variables are not suitable here because they do not summarize a single quantitative variable's distribution effectively.