The logistic growth function f (t) = models the number of people who have become ill with a particular infection t weeks after its initial outbreak in a particular community. How many people were ill after 9 weeks?

The function is supposed to be

f (t) = 87000 / (1+1449e^-1.2t)

We can find the number of people ill after 8 weeks using the function above. We simply have to substitute 9 into t and solve for f (t)

f (9) = 87000 / (1 + 1449e^-1.2 (9))

f (9) = 84,502

After 9 weeks, there will be 84,502 infected people