Question

The population of a city in Alabama increases every year by 11.5 percent. If the population in 2011 was 4.8 million, what will its population be in 2016?

Answer 1

To calculate the population in 2016, we shall proceed as follows;
population growth follows an exponential growth formula given by:
f(t)=ae^(kt)
where:
f(t)=future population
a=initial population
k=constant of proportionality;
suppose in 2011, t=0 and in 2016, t=5; k=11.5%=0.115, a=4.8 million
thus the population in 2016 will be:
f(t)=4.8e^(0.115t)
thus;
f(5)=4e^(0.115*5)
=22.44
N/B the population is in millions
thus;
the population in 2016 will be:
22.44 million