To determine who spends less time doing their homework per night, we can calculate the average number of hours spent on homework per day for both Marco and Maribella based on the data provided.
Marco's Average Homework per Day:
- For 3 days: 3.25 hours / 3 days = 1.08 hours/day
- For 9 days: 9.75 hours / 9 days = 1.08 hours/day
- For 12 days: 13.0 hours / 12 days = 1.08 hours/day
- For 30 days: 32.5 hours / 30 days = 1.08 hours/day
Marco spends approximately 1.08 hours on homework per day.
Maribella's Average Homework per Day:
- For 4 days: 4.2 hours / 4 days = 1.05 hours/day
- For 8 days: 8.4 hours / 8 days = 1.05 hours/day
- For 20 days: 21.0 hours / 20 days = 1.05 hours/day
- For 28 days: 29.4 hours / 28 days = 1.05 hours/day
Maribella spends approximately 1.05 hours on homework per day.
Conclusion: Maribella spends less time on homework per night (1.05 hours) compared to Marco (1.08 hours).
Therefore, the correct statement is: Maribella spends less time on homework per night.