1. A survey shows that teachers divide each 80-minute class period as follows: 20 minutes for homework review; 30 minutes for lecture; 30 minutes for activities. If there are 4 periods each day, each of which is 80 minutes, how much time does a teacher spend doing homework review during a 5-day week?
Answer: B
Teachers spend 6 hours and 40 minutes doing homework review during a 5-day week.
In a 5-day week, a teacher dedicates a total of 100 minutes to homework review per day, resulting in 6 hours and 40 minutes over the entire week.
A) 6 hr 23 min
This option is incorrect as it underestimates the total time spent on homework review. With 20 minutes allocated per class and 4 classes a day, the total for one day is 80 minutes, which over 5 days equals 400 minutes or 6 hours and 40 minutes, not 6 hours and 23 minutes.
B) 6 hr 40 min
This option is correct as it accurately reflects the total amount of time spent on homework review. With 20 minutes spent per class for 4 classes each day, the calculation yields 80 minutes daily. Over 5 days, this totals to 400 minutes, which converts to 6 hours and 40 minutes.
C) 6 hr 55 min
This option is incorrect as it overestimates the total time for homework review. The correct calculation shows that the total time spent in a week is 6 hours and 40 minutes, not 6 hours and 55 minutes.
D) 6 hr 7 min
This option is also incorrect, as it significantly underestimates the time spent on homework review. The total of 400 minutes is equal to 6 hours and 40 minutes, far exceeding 6 hours and 7 minutes.
Conclusion
The correct answer of 6 hours and 40 minutes accurately reflects the cumulative time allocated for homework review over the week. All other options fail to match the correct calculation based on the time spent per class and the number of class periods in a week. Thus, option B is definitively the right choice.