Algebra-1

Question Analysis
This question involves combining frequencies of intervals that meet a condition ("6 or fewer hours") from a grouped frequency table.
The main focus is on identifying which intervals qualify and summing their frequencies.

Key Concept Explanation
Grouped Frequency: When data is divided into intervals (e.g., "1–3 hours"), the frequency of an interval is the number of data points in that range. To find the total for a condition like "6 or fewer hours," sum the frequencies of all intervals that fall within that range.

Step-by-Step Solution
Identify intervals with 6 or fewer hours: "1–3 hours" and "4–6 hours" (since 6 is the upper limit of the second interval...