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?

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