Given details are,
Annual increase rate of population of city is = 4%
Population in 1999 was = 6760000
(i) Population of the city in 2001 (2 years after)
By using the formula,
A = P (1 + R/100)
x = 6760000 (1 + 4/100) (1 + 4/100)
= 6760000 (104/100) (104/100)
= 6760000 (1.04) (1.04)
= 7311616
∴ Population in the year 2001 is 7311616
(ii) Population of city in 1997 (2 years ago)
By using the formula,
A = P (1 + R/100)
x = 6760000 (1 – 4/100) (1 – 4/100)
= 6760000 (96/100) (96/100)
= 6760000 (0.96) (0.96)
= 6230016
∴ Population in the year 1997 was 6230016.