Final answer:
After 20 hours, there are 1326 acres left to mow; after 100 hours, 1230 acres are left; and it takes 1125 hours to mow all lawns.
Step-by-step explanation:
The question involves the use of a linear equation to determine the acreage of land left to mow after a given number of hours, as well as solving for the number of hours needed to mow the entire area. The equation given is ý = 1350 - 1.2x, where x represents the number of hours of work and ý represents the number of acres left to mow. To find answers to the questions, we just need to substitute the value of x and solve for ý.
31. Acres left after 20 hours of work:
To find the acres left to mow after 20 hours of work, we substitute x = 20 into the equation:
ý = 1350 - 1.2(20)
ý = 1350 - 24
ý = 1326 acres left to mow
32. Acres left after 100 hours of work:
Substitute x = 100 into the equation:
ý = 1350 - 1.2(100)
ý = 1350 - 120
ý = 1230 acres left to mow
33. Hours to mow all the lawns:
To find the time it takes to mow all the lawns, or when ý = 0, set the equation to zero and solve for x:
0 = 1350 - 1.2x
1.2x = 1350
x = 1125 hours to mow all lawns