The population of a city increases each year by 4% of what it had been at the beginning of each year.
Question:
The population of a city increases each year by 4% of what it had been at the beginning of each year. If the population in 1999 had been 6760000, find the population of the city in
(i) 2001
(ii) 1997.
Solution:
(i)
Population of the city in $2001=P\left(1+\frac{R}{100}\right)^{2}$
$=6760000\left(1+\frac{4}{100}\right)^{2}$
$=6760000(1.04)^{2}$
$=7311616$
Thus, Population of the city in 2001 is 7311616 .
(ii)
Population of the city in $1997=P\left(1+\frac{R}{100}\right)^{-2}$
$=6760000\left(1+\frac{4}{100}\right)^{-2}$
$=6760000(1.04)^{-2}$
$=6250000$
Thus, Population of the city in 1997 is 6250000 .