180 Days of Ideas for Discussion in Math Class.
(as of 9July2014, we're in overtime!)
Population of organism after n min is P(n)=k•9^(n/2)
— David Marain (@dmarain) April 30, 2015
Thanks for posting this! Your question is better expressed than mine (more 'real-world'). Furthermore my suggested solution was uninspired. Much better to rewrite 9^(n/2) as 3^n...