The population of a species has been modelled by the equation P=I.3^(kt) where t is the elapsed time in days and I is the population at t=0.
If the population has increased by a factor of 9 in 8 days, by what factor will it have increased over 12 days?
If the population has increased by a factor of 9 in 8 days, by what factor will it have increased over 12 days?