Question

if the population size of the world is increasing at a rate of 0.5% per year, how long does it take until the world population doubles in size? round your answer to the nearest tenth.

Answer 1

Using the Rule of 70, the world population will take approximately 140 years to double if the growth rate remains constant at 0.5% per year.

Step-by-step explanation:

To calculate the time it takes for the world population to double in size with an annual growth rate of 0.5%, we use the Rule of 70, which is a simplified way to determine the doubling time of an investment's growth based on its compounded interest rate. The Rule of 70 states that we can divide the number 70 by the annual growth rate to find the doubling time.

The formula is as follows:

Doubling time (in years) = 70 ÷ growth rate (in percent)

So, for a 0.5% growth rate:

Doubling time = 70 ÷ 0.5 = 140 years

Therefore, it will take approximately 140 years for the world population to double if the growth rate remains constant at 0.5% per year.