Approximately how long would it take for real GDP to double if it grew at a constant annual rate of 2 percent?
A)Approximately 72 years.
B)Approximately 36 years.
C)Approximately 2 years.

Question

Quizplus · Accepted Answer

This is a classic example of the rule of 70, which estimates the number of years it takes for a variable to double based on its growth rate. To apply this rule, divide 70 by the growth rate. In this case, 70/2 = 35. Therefore, it would take approximately 35 years for real GDP to double at a constant annual rate of 2 percent. However, since this is an estimation, answer B is the closest option to the correct answer.

Approximately How Long Would It Take for Real GDP to Double