Question

The population of a town doubled every 5 years from 1960 to 1975. What is the percentage increase in population in this period?

Answer 1

Let the population in 1960 be x
After 5 yrs that is in 1965 population = 2x (since it is doubled)

After 5 next yrs in 1970 population doubled = 2 × 2x = 4x

Next 5 yrs in 1975 population = 4x × 2 = 8x


So first population is x
last population 8x

percent =
$\frac{8x}{x} \times 100 \\ \\ = 800\%$
Hope it helps dear friend ☺️✌️✌️