Question

The population of a city increases by 30% every year. If the present population is 338000, then What was the population of the city two years ago?

Answer 1

Let initial population be $p$

As population increased by $30\%$ per year.

So, population after $2$ years

$=p(1+\frac{30}{100}{)}^2$
$=p(1.3{)}^2$

Given that ,$338000=1.69p$
$⟹p=\frac{338000}{1.69}$
$⟹p=2,00,000$

So, population two years ago$=2,00,000$