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 with these two classes.
She spends a total of 8 * 7 = <<8*7=56>>56 hours sleeping each week.
When you add up all of her sleep and study time, it equals 56 + 8 + 21 = <<56+8+21=85>>85 hours.
In one week, Lisa has 168 - 85 = <<168-85=83>>83 hours left for work and other activities.
Let x be the number of hours Lisa can work each week.
The inequality to represent the maximum number of hours Lisa can work is x ≤ 83.
The maximum number of hours Lisa can work is 83. Answer: \boxed{83}.
To determine the maximum amount of time Lisa can work each week, we need to consider her existing commitments and the total number of hours available in a week.
Here's a breakdown of her commitments:
1. Homework: 21 hours
2. Classes: 4 hours (Tuesday) + 4 hours (Thursday) = 8 hours
3. Sleep: 8 hours per day * 7 days = 56 hours
Total committed hours = 21 + 8 + 56 = 85 hours
Given that there are 168 hours in one week, we can write the following inequality to find the maximum amount of time Lisa can work:
Let x represent the number of hours Lisa can work each week.
x + 85 ≤ 168
Now, we can solve this inequality to find the maximum amount of time Lisa can work each week.
x ≤ 168 - 85
x ≤ 83
Therefore, Lisa can work at most 83 hours each week.
To determine the maximum amount of hours Lisa can work each week, we need to consider her time commitments for classes, homework, sleep, and the total number of hours in a week.
1. Lisa has two classes, each lasting 4 hours, one on Tuesday and one on Thursday. So, the total amount of time for classes in a week is 4 hours + 4 hours = 8 hours.
2. Lisa sets aside 21 hours for homework each week.
3. Lisa wants to ensure 8 hours of sleep each night. In a week, this amounts to 8 hours x 7 days = 56 hours.
4. The total number of hours in one week is 168 hours.
Now, to find the maximum amount of time Lisa can work each week, we need to subtract the time she spends on classes, homework, and sleep from the total number of hours in a week and set it as an inequality:
Let "x" be the number of hours Lisa can work.
x ≤ 168 hours - (8 hours + 8 hours + 21 hours + 56 hours)
x ≤ 168 hours - 93 hours
x ≤ 75 hours
Therefore, Lisa can work at most 75 hours each week.