(c) The demographic data for country X for the year 2020 is provided in the table below.

Crude birth rate 381,000individuals
Crude death rate 241,000individuals
Net migration rate 21,000individuals
(i) Calculate the national population growth rate for country X. Show your work.

(ii) Using the rule of 70, calculate the doubling time for this population.

The growth rate is 66.80%

The population would double in 1.05 years

Explanation:

The applicable formula here in determining the growth rate is to have  the present population(birth rate+net migration rate) on one hand which is then equated to crude death rate multiplied by the growth factor(1+r)^n

381,000+21000=241000*(1+r)^n

r is the unknown growth rate

n is the number of years the growth rate relates to,which is one year since the figures given relate only to 2020

402000=241000*(1+r)

1+r=402,000/241,000

r=(402,000/241,000)-1=66.80%

The growth rate is 66.80%

Using the rule of 70 which implies that the population would double its present figure  when 70 is divided by the growth rate of the population:

=70/66.80=1.05 years