Question

The number of people living on a remote island decreases by 9% every 10 years. In 1950 there were 18000 living on the island. Calculate how many less people will be living on the island in 2020.

Answer 1

Answer: 9,301 people

Explanation:

First find the number of years that have passed:

= 2020 - 1950

= 70 years

Population decreases every 10 years so in 7 years it would have increased:

= 70/10

= 7 times

In 2020 therefore:

= 18,000 * (1 - 9%)⁷

= 9,301 people