Question

If the doubling time for the world’s population is 56 years, what will be the growth rate over this time period?

a) Growth Rate = 1.24%
b) Growth Rate = 1.25%
c) Growth Rate = 1.26%
d) Growth Rate = 1.27%

Answer 1

Using the Rule of 70, which divides 70 by the doubling time, the growth rate for a doubling time of 56 years is calculated to be approximately 1.25%, corresponding to answer choice b).

Step-by-step explanation:

To find the growth rate associated with a given doubling time, we can use the Rule of 70, which states that dividing 70 by the doubling time gives the approximate annual percentage growth rate. In this case, the doubling time for the world’s population is 56 years. Therefore, the growth rate can be calculated as follows:

Growth Rate = 70 / Doubling Time = 70 / 56 ≈ 1.25%

Therefore, the correct answer to the student's question is b) Growth Rate = 1.25%.