Question

F(t)= 30000/1+20e^-1.5t

Describes the number of people, f(t), who have become ill with influenza t weeks after the initial outbreak in a town with 30,000 inhabitants.
a.) How many people became ill with flu when the epidemic began?
b.) How many people were ill by the end of the fourth week?

Answer 1

Surely you meant:

F(t)= 30000/(1+20e^-1.5t )

a) let t = -
F(0) = 30000/(1+20) = appr 1429

b) when t = 4
F(4) = 30000/(1 + 20e^-6)
= 28,583

check my "button-pushing" on the calculator

Answer 2

f(t) 30000
1+20e^-1.5(t)