Question

The number of wolves in a wildlife preserve is estimated to have increased continually by 3% per year. If the population is now estimated at 5,400 wolves, how many were present 10 years ago?

Answer 1

For the answer to the question above, Well, first let us put up a functional equation. 
Since this is an exponential function, it'll be: f(t)=54,000*1.03^t 
But we want to know how many wolves there were 10 years ago. 
For that, we simply "turn time around", as in: f(t)=54,00*1.03^-t 
This displays a decreasing number of wolves, as you turn back time. 

Now we simply calculate 54,000*1.03^-10 
which is approximately 40,200?