n >= 1125 First, make an equation to express the money raised after expenses. 55n - 15n + 10000 = m The above expression can be read as "55 dollars per running is raised, but 15 dollars is spent per running to support them. Plus we get 10000 as a constant regardless of how many runner we have." Now convert that to an inequality for at least 55000 to be raised. 55n - 15n + 10000 >= 55000 Now solve for n 55n - 15n + 10000 >= 55000 40n + 10000 >= 55000 40n >= 45000 n >= 1125 So there needs to be at least 1125 runners in order to meet the goal of $55,000.