91影视

Economists use the concept 鈥渞ule of 70鈥� to evaluate the approximate number of years an economy will take to double its size. The mathematical expression under the rule of 70 is given below:

$ApproximatenumberofyearsrequiredtodoubletherealGDP=\frac{70}{Annualpercentagerateofgrowth}$

The required annual growth rate for a country to double its output can be calculated by using the 鈥渞ule of 70鈥� formula.

• The required annual percentage growth for a country to double its output in 7 years is:

$$\begin{gathered} Annualpercentagerateofgrowth=\frac{70}{7} \\ =10percent \end{gathered}$$

The required annual growth rate is 10 percent.

• The required annual percentage growth for a country to double its output in 7 years is:

$$\begin{gathered} Annualpercentagerateofgrowth=\frac{70}{35} \\ =2percent \end{gathered}$$

The required annual growth rate is 2 percent.

• The required annual percentage growth for a country to double its output in 7 years is:

$$\begin{gathered} Annualpercentagerateofgrowth=\frac{70}{70} \\ =1percent \end{gathered}$$

The required annual growth rate is 1 percent

• The required annual percentage growth for a country to double its output in 7 years is:

$$\begin{gathered} Annualperce\tan gerateofgrowth=\frac{70}{140} \\ =0.5percent \end{gathered}$$

The required annual growth rate is 0.5 percent.