If a country's income grows at the rate of 5 percent a year,it doubles in about
A)eight years.
B)six and one-half years.
C)ten years.
D)fourteen and one-half years.
E)twenty years.

Question

Quizplus · Accepted Answer

The Rule of 70 is used to estimate the number of years it takes for a quantity to double, given a constant annual growth rate. By dividing 70 by the growth rate (5% in this case), we get 70/5 = 14 years. Therefore, the income doubles in about fourteen and one-half years.

If a Country's Income Grows at the Rate of 5