exponential formula help needed

Question

Write an exponential formula of the form f(t)=a times b^t to represent the following situation, assume t is in years

The beginning population is 79,000 decreasing by 1.99% annually

f(t)=

Answer 1

We start with P=79000, in which we are decreasing at a rate of r=0.0199, so the decay factor is 1-r = 1-0.0199 = 0.9801:

The function f(t) = 79000(0.9801)^t best describes this relationship. What's going on here is that every year, 98.01% of the population in that year is kept, starting at 79000 people at year t=0.

Hope this helped!