a town has a population of 4000 and grows 2% every year. to the nearest year, how long will it be until the population will reach 6400?
Future Population =FP
Present Population=PV
FP =PV x [1 + R]^N, where R=Rate of growth, N= Number of Periods.
6400 = 4000 x 1.02^N
6400/4000 = 1.02^N
1.6 = 1.02^N Take the log of both sides
N =Log(1.6) / Log(1.02)
N =23.73 =~24 Years for town's population to grow from 4000 to 6400.