Answer
The cost of removing $60\%$ of the pollutants from the bayou is $\$150,000$.
The cost becomes $\$400,000$ when $80\%$ of the pollutants are removed.
Work Step by Step
(i)
To find cost of removing $60\%$ of the pollutants, substitute 60 to x to have:
$f(60)=\dfrac{100,000(60)}{100-60}=\dfrac{6,000,000}{40}=150,000$
Thus, cost of removing $60\%$ of the pollutants from the bayou is $\$150,000$.
(ii)
To find cost of removing $80\%$ of the pollutants, substitute 80 to x to have:
$f(20)=\dfrac{100,000(80)}{100-80}=\dfrac{8,000,000}{20}=400,000$
Thus, cost of removing $80\%$ of the pollutants from the bayou is $\$400,000$.
