The population of a village has increased annually at the rate of 25%. If at the end of 3 years it is 10,000, the population in the begining of the first year was:

5120

Let the population in starting = x

ATQ,

⇒ x × \(\frac{125}{100}\) × \(\frac{125}{100}\) × \(\frac{125}{100}\) = 10,000 (After 3 year)

⇒ x × \(\frac{5}{4}\) × \(\frac{5}{4}\) × \(\frac{5}{4}\) = 10,000

⇒ x = 10,000 × \(\frac{4}{5}\) × \(\frac{4}{5}\) × \(\frac{4}{5}\)

⇒ x = 5120