Lisa is taking two classes at a local community college. She sets aside 21 hours for homework a week with these two classes. The two classes are 4 hours each once a week on Tuesday and Thursday. She wants to get a part-time job and ensure 8 hours of sleep each night. There are 168 hours in one week. How many hours can she work at most each week? Write and solve an inequality to determine the maximum amount of time she can work each week.
Lisa spends a total of 4 + 4 = <<4+4=8>>8 hours in class each week.
She has 168 – 8 – 8 – 21 = <<168-8-8-21=131>>131 hours left.
She needs 8 * 7 = <<8*7=56>>56 hours of sleep each week.
She can spend 131 – 56 = <<131-56=75>>75 hours on work. Answer: \boxed{75}.
To determine the maximum amount of time Lisa can work each week, we need to subtract the time she spends on homework, sleep, and attending classes from the total number of hours in a week.
Total hours in a week: 168 hours
Hours spent on homework: 21 hours (2 classes x 4 hours per class x 1 day per week)
Hours spent attending classes: 4 hours + 4 hours = 8 hours (2 classes x 4 hours per class)
Hours spent sleeping: 8 hours x 7 days = 56 hours (assuming 8 hours of sleep each night)
To find the maximum amount of time Lisa can work each week, we subtract the time spent on homework, attending classes, and sleeping from the total number of hours in a week.
Maximum work hours = Total hours - Homework hours - Class hours - Sleep hours
Maximum work hours = 168 hours - 21 hours - 8 hours - 56 hours
Simplifying the equation:
Maximum work hours = 168 hours - 21 hours - 8 hours - 56 hours
Maximum work hours = 83 hours
Therefore, Lisa can work at most 83 hours each week.
To determine the maximum amount of time Lisa can work each week, we need to subtract the hours she spends on her classes, homework, and sleep from the total number of hours in a week.
We know that Lisa spends 21 hours on homework each week, which takes up some of her free time.
Each class lasts for 4 hours and there are two classes per week (on Tuesday and Thursday). So the total time Lisa spends on classes is 4 x 2 = 8 hours.
She also wants to ensure 8 hours of sleep each night, which adds up to 8 x 7 = 56 hours of sleep per week.
Now, let's calculate the total time spent on classes, homework, and sleep:
Homework: 21 hours
Classes: 8 hours
Sleep: 56 hours
The total time spent on these activities is 21 + 8 + 56 = 85 hours.
To determine the maximum amount of time Lisa can work each week, we subtract the time spent on these activities from the total number of hours in a week.
Total hours in a week: 168 hours
Maximum work hours = Total hours - Time spent on activities
= 168 - 85
= 83 hours
Therefore, the maximum amount of time Lisa can work each week is 83 hours.
To write an inequality for this problem, let's assume that the maximum work hours is represented by the variable w.
The inequality can be written as:
w ≤ 83
This means that Lisa can work at most 83 hours each week.