Question

the population of town is 8125. if annual birth rate is 7% and annual death rate is 3%, calculate the population after 2 years.

Answer 1

Net birth rate = Annual birth rate - annual death rate = 7 -3 = 4%

This problem is similar to compound intrest calculated annually

There , amount A for a principal P after n years = $P(1+r)^{n}$

where , r is rate of intrest in percentage

similar to it ,

Net birth rate can be taken as Rate of intrest
Present population as Principal


Net birth rate in percentage = 0.04

So , population after 2 years=8125 * ( 1 + 0.04 )^2

                                             = 8788.

Answer 2

I hope 8788 is answer.