Question

the population of a village 3 years ago was 505000. due to migration to cities, it decreases at the rate of 10% every year. find the decrease in its population in the last 3 years

Answer 1

let, the population of city be principal
Principal= 505000
Rate =10 per cent
year=3
Amount= P(1-R/100)^n
= 505000(1-10/100)^3
= 505000*90/100*90/100*90/100
= 368145
368145 population after 3 years

population decreases = P - A
= 505000 - 368145
= 136855

I hope it is right.....

Answer 2

Given :

The population of a village 3 years ago was 505000.

It decreases at the rate of 10% every year.

To Find :

find the decrease in its population in the last 3 years

Solution:

The population of a village 3 years ago was 505000.

It decreases at the rate of 10% every year.

Formula $:N(t)=N_0(1-r)^t$

N(t)=Population after t years

N = Initial population

r = rate of decrease

t = time

So, decrease in population after 3 years = $505000(1-0.1)^3=368145$

Hence The population  after 3 years is 368145