Under a simple rate of growth, the population (P units) of a city becomes 1.5 times P in 10 years. In how many years, the population of the city would become double (2 times P) under the same growth rate?
Show answer & explanation
Correct answer: A
Explanation
The correct answer is Option 1 i.e. 20.
The population (P units) of a city becomes 1.5 times P in 10 years
Hence, 0.5 times increament in 10 years
Because the growth rate will be same then, after every 10 years 0.5 times will be increases
So, in next 10 years 0.5 will increase and it becomes 2P
So, the population of the city will be 2P in 20 years