The Purplemath Forums

Need some help on a geometric progression problem to solve for the number of periods. Here is the problem: A rabbit farm has 2000 rabbits in the first period. Each month 20 rabbits are added by the game warden. In addition, the population grows by 3% per month by reproduction. How many months does i...

I was using the following formula: Sn = a[(1-r^n)/(1-r)] where a is a for the first period i.e. 2000 rabbits in this case. 5000 is Sn as it is the total rabbits at the end number of periods. The goal is to solve for n or the number of periods required to get to 5000. r is the rate of increase or 3% ...

No, the population of rabbits starts at 2000 and 20 are added every month and each of the rabbits reproduces by 3% every month. I would assume that the rabbits added are reproducing each month as well I just cannot develop a proper formula that will allow me to figure out how many months it takes al...