Answer:
A country currently has a population of 100 million and an annual growth rate of 3.5 percent. If the growth rate remains constant, the population of this country in 40 years will be (D) 400 million
Explanation:
Growth Rate is given in %, which means amount of growth in a year. If a country have population of 100 and growth rate is 2%, then next year population will be 102.
The population for the next consequent year will be [tex](102+((\frac{2}{100})\times102))[/tex], and so on. So this is the question of compounding every year.
So we have a direct formulae for the same. Let us assume population to be P, Growth rate to be R
So population after n years [tex]= P ((1+\frac {R}{100})^n)[/tex]
Entering the values in the formulae,
Population after 40 years
[tex]= 100 \times ((1+\frac {3.5}{100})^{40})[/tex]
= 400 million
Thus, the population of country after 40 years will be 400 million.
